What is the difference between the word that and which

If you aren’t sure when to use which vs. that in your writing, don’t feel bad. They are one of the most common questions I get from readers, wondering when it is correct to use which word.

Which and that are both complicated words in English with many different uses inside a sentence. And while they both can be used in other constructions, the confusion between the two usually centers on their uses as relative pronouns. If you’re not sure what these are, don’t worry; everything you need is explained below.

What is the Difference Between Which and That?

Many people say the differences between these two words aren’t really differences at all. Still, many people yet swear by the traditional rule I will outline below.

That and Which as Pronouns

A brief, important note on using which or that as pronouns: be careful when using them to refer to people. Many style guides specify writers to solely use who when referring human beings and/or animals with a name. For example,

• The woman who opened the door for you is my mom. (CORRECT)
• The woman that opened the door for you is my mom. (WRONG)

Which and that are used, instead, for inanimate objects or animals without a name. For example,

• The car, which had already ran out of gas, now has a flat tire.
• The bat that I threw hit the bleachers.
• I am sick of the dog that keeps barking.

This rule is followed by the AP Stylebook but not the Chicago Manual of Style. It’s not clear that it’s absolutely necessary, but if you are writing a paper or any piece of formal writing, it’s probably best to observe the rule.

When to Use That

The traditional American English rule regarding that and which states that that should be used with restrictive clauses and which should be used with nonrestrictive clauses.

A restrictive clause is one that is essential to the meaning of a sentence. They are also sometimes called essential clauses. A restrictive clause is used to narrow a category or identify a particular item being talked about. It restricts the meaning, making it more specific. For example,

• All bags that are over 50 pounds will not be permitted.

The words that are over 50 pounds restrict the kind of bags you are talking about by making your sentence more specific. Without them you would be saying that no bags are permitted at all.

You should also note that restrictive clauses are not set off by commas.

When to Use Which

While that is used restrictively, which is used nonrestrictively with nonrestrictive clauses.

A nonrestrictive clause is one that is nonessential to meaning of the sentence. If you removed it, the sentence would still be understood. This doesn’t mean they are pointless; nonrestrictive clauses add some bit of extra information to the sentence. For example,

• My bedroom, which is on the second floor, is very messy.

The words which is on the second floor add an extra piece of information about my bedroom. But if you were to remove them from the second, you would still understand that my bedroom is messy.

Nonrestrictive clauses, since they are parenthetical in nature, are always set off by commas. As you see above, there is a comma before which and after floor. These commas are very important because they can change the entire meaning of a sentence should you not have them in place.

The Chicago Manual of Style holds that which can be used restrictively when it is preceded by a preposition. For example,

• The situation in which you put us is very dangerous.
• The school from which I graduated is very prestigious.

Why You Need To Use That and Which Correctly

Restrictive clauses (or essential clauses) do not have commas introducing or surrounding them, but nonrestrictive (or nonessential clauses) do have commas introducing or surrounding them.

Now, as I said above, misplacing a comma when you are dealing with restrictive and nonrestrictive clauses can change the entire meaning of your sentence. The same goes for using that when you really mean which. For example, consider the following sentences,

• My dirt bike that is green goes really fast.
• My dirt bike, which is green, goes really fast.

The first sentence suggests that we might have more than one dirt bike and that out of our collection the green one is the fast one.

The second sentence, since the words which is green can be removed, simply informs the reader that my dirt bike is green, and it can go really fast.

It should be noted, however, that the commas in these sentences are really doing the brunt of the work, not necessarily the words which and that.

Quiz and Sentence Examples

Below are a few sentences you can use to practice,

1. My mother was a great woman ______ always helped me with my writing.
2. The year ______ our daughter was born was a great year.
3. This book, ______ was written last November, is a great read.
4. Any book ______ gets them reading is worth having.
5. He scored 81 points in that game, ______ is hardly an easy accomplishment.

Display the answers below

Remember the Difference

A good way to remember when to use that vs. which is that “which clauses” can be removed from the sentences. You could say that you can throw out the “whiches” and no meaning will be lost.

The “thats,” however, cannot be removed from your sentences without changing the meaning.

A Note on British English Usage

I began by saying that this is a standard American English rule. In British English, writers seldom observe the distinction between that vs. which, and even though Fowler’s Usage Guide recognizes that much is to be gained by recognizing the distinction, not all British writers do.

Summary

That and which should not be used to refer to people.

That is reserved for restrictive clauses, essential to a sentence’s meaning.

Which is used with nonrestrictive clauses, nonessential to a sentence’s meaning.

Answers

1. Who
2. That
3. Which
4. That
5. Which

В английском полно слов-определителей и вопросительных слов, с которыми все не так просто. Например, у what и that разница не столько в буквах, сколько в смыслах, хотя на русский они оба переводятся, как «что».

Но русский перевод лучше оставить в стороне. Здесь главное уловить истинное значение и связь между этими английскими словами, а уж на родном языке можно как угодно сказать — и «что», и «который», и «какой».

That и which как относительные местоимения

Чтобы понять ту роль, которую играют иногда that и which, нужна небольшая грамматическая справка.

Относительные местоимения (relative pronouns на английском) — это такие слова, которые нужны, чтобы связать две части предложения. Одна его часть обычно называет объект (о чем или о ком говорится), а вторая дает о нем какие-то подробности.

Относительные местоимения в английском бывают следующие:

Who — кто

Whom — кого

Whose — чей

Which — который

That — который

• Who и whom используются, когда мы говорим о людях:

The girl who played with fire.

Девочка, которая играла с огнем.

• Which — о вещах:

Facebook blocked the pages which I liked.

Фейсбук заблокировал страницы, которые я лайкнул.

• That — и о том, и о другом.

The girl that I like.

Девушка, которая мне нравится.

The idea that I cannot accept.

Идея, которую я не могу принять.

Relative pronouns используются:

• После существительного, чтобы уточнить, какой человек (предмет) имелся в виду.

The money that I earned.

Деньги, которые я заработал.

The man who changed the world.

Человек, который изменил мир.

• Чтобы дать больше информации о предмете или человеке (в этом случае нельзя употреблять that) :

My aunt, who is 69, still works as a teacher.

Моя тетя, которой 69 лет, все еще работает учителем.

The house, which is owned by Santa is in Lapland.

Дом, которым владеет Санта, находится в Лапландии.

Остановимся на местоимении that.

Когда в предложении встречается that, это значит, что до этого момента уже было упомянуто что-то, о чем шла речь. «That» используется, чтобы описать и определить вещь, про которую вы УЖЕ говорили.

Например:

Where is the book? (Где книга?)
Which book? (Какая книга?)
The book that I was reading. (Книга, которую я читал).

I saw that movie. (Я видел то кино).
Which movie? (Какое кино?)
The movie that you were talking about. (Кино, про которое ты мне рассказывал).

«That» определяет предшествующее существительное и соединяет объект, упомянутый ранее, с другими членами предложения.

То есть, в примере

The car that cost me around 10000 Euros.

Машина, которая стоила мне около 10000 евро,

До того уже была упомянута машина, именно поэтому дальше идет that.

Употребление what и which в вопросах. Разница между which и what.

Основная функция слова what — задавать вопросы, начинающиеся на «что?», «какой?».

Примеры вопросов:

What is he doing? (Что он делает?)

What is love? (Что такое любовь?)

What are your hobbies? (Какие у тебя хобби?)

Which — более формальный способ задать похожий вопрос. Особенно часто это слово употребляется, когда нужно выбрать из нескольких вариантов. В русском ему соответствуют вопросительные слова «который?» «какой именно?»

Можно заменить which с помощью what, и ошибки не будет.
Например:

Which of the following answers is true?

Какой из следующих ответов правильный?

В этом предложении определенно есть ситуация выбора, поэтому which идеально подходит. С what предложение тоже «работает»:

What of the following answers is true?

Но наоборот сделать получается не всегда. Если мы захотим изменить

What is your name? (дословно: какое твое имя?)

на

Which is your name?

это будет иметь смысл только в том случае, если есть список с именами, и говорящий показывает его собеседнику и просит сделать выбор.

Отличие what от that

Мы уже сказали, что с what часто начинаются вопросы.

Но это слово встречается и в утвердительных предложениях. И если в них нет ответа на вопрос «что?», то эту недостающую информацию можно заменить местоимением what:

What he did was terrible.

То, что он сделал, было ужасно.
(Что он сделал? Покормил аквариумных рыбок кошачьим кормом? Надел носки разного цвета? Мы не знаем, поэтому используем what).

Обычно, говоря «what» подразумевают «вещь, которая», или «то, что».

What you need is a cup of strong hot coffee.
(Та вещь, которая тебе нужна — чашка крепкого горячего кофе).

Возьмем фразу:

What I’m going to tell you is very important.

(То, что я собираюсь тебе рассказать, очень важно).

Неизвестно, что автор собирается рассказать. Поэтому он использовал what.

Но почему бы не сказать:

That I’m going to tell you is very important?

That, как мы знаем, используется после существительного, когда мы уже знаем, о чем идет речь. Поэтому ни с того, ни с сего, без контекста, это местоимение просто не воспринимается.

А что, если мы изменим этот пример, и добавим существительное перед местоимением? Сможем ли мы тогда использовать that?

The secret that I’m going to tell you about is very important.

Секрет, о котором я тебе расскажу, очень важный.

Получилось! Поставив существительное «секрет» в начало предложения, мы сделали возможным использование that.

Итак, что же нового мы сегодня узнали?

• That и which могут связывать части предложения и переводиться, как «который».
• Which в вопросительных предложениях подразумевает ситуацию выбора.
• That говорит об определенности, о том, что предмет разговора нам знаком.
• What используется там, где есть недостаток информации.

The standard rule of grammar is that the usage of that vs. which depends upon whether the following clause is restrictive or non-restrictive.

«That» is used to indicate a specific object, item, person, condition, etc., while «which» is used to add information to objects, items, people, situations, etc. Because «which» indicates a non-restrictive (optional) clause, it is usually set off by commas before «which» and at the end of the clause.

Rule for using That instead of Which

The general rule requires that you use that only to introduce a restrictive (or defining) relative clause, which identifies the person or thing being talked about. For example,

The building that I was telling you about is just down the road. 

In this sentence, the phrase that I was telling you about specifically identifies the object in the previous phrase (building) and is a restrictive clause. In this use, that should never be preceded by a comma because the word is an integral (non-optional) part of the description.

Similar examples include:

• My books that have red covers are new.
• The classes that are held every Monday start at 9:00 AM.

Note that the subject of the restrictive clause can change «that» to «who», «when» and «where» for correct usage. Use who for a person, when for a time period and where as a substitute for «that place». For example:

• The man who shot Lincoln jumped onto the theater’s stage.
• Remember the time when I fell off the ladder?
• Billy went to where they sell turkey eggs.

Rule for using Which instead of That

On the other hand, use which with non-restrictive (or non-defining) clauses. These are clauses providing additional information about something that has already been identified in the context. In this use, which is always preceded by a comma and a comma is placed after the restrictive clause ends (if the sentence continues). For example,

• My new books, which have black covers, are on the desk.
• The padded chairs, which are on the second floor, have to be replaced.

When the clause is at the end of the sentence, only one comma is used, before which:

The students in Chemistry 101 have been complaining about the textbook, which is hard to follow.

In this case, the clause which is hard to follow is descriptive, not restrictive i.e. it does not specify which text is being complained about (although it can be easily inferred). For these cases, which sounds more natural than that.

Some grammarians extend the rule and insist on that being used only in restrictive clauses, while which should be used only in nonrestrictive clauses. For example:

Wrong, according to strict grammarians: I need a book which will tell me all about city gardening. 

Correct usage: I need a book that will tell me all about city gardening.

The use of which with restrictive clauses is fairly common, even in edited prose. However, the American Psychological Association (APA), in its 6th edition Manual, recommends adhering to the rule and use that for all restrictive clauses.

Which can be especially useful where two or more relative clauses are joined by and or or. For example,

Politics is an environment in which ordinary people may succumb to greed and which many have found reason to hate.

You may also want to use which to introduce a restrictive clause when the preceding phrase contains a that or a those. For example,

• We want to fund only those initiatives which will increase revenues and customer satisfaction.
• Mrs. O’Reilly likes that new Italian restaurant which is located downtown.

Using That and Which together

The words that and which can also be used together. In doing so, that serves to emphasize the descriptive clause introduced by which. For example,

Reality is that which, when you stop believing in it, doesn't go away.

GMAT Test Questions

The Graduate Management Admission test (GMAT) has a Sentence Correction section. To improve your chances at properly selecting the right answer between that and which, use this technique:

1. Does eliminating the clause change the meaning of the sentence? Use THAT.
2. If the meaning doesn’t change, does the clause describe something more about the subject? Use WHICH.

Examples:

• The Grand Canyon is a U.S. National Park that/which is in Arizona. [Use which]
• My brother doesn’t like sports that/which are played indoors. [Use that]

References

• That — Wiktionary
• Which — Wiktionary