What does of mean in a word problem

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Every teacher wonders how to teach a word to students, so that it stays with them and they can actually use it in the context in an appropriate form. Have your students ever struggled with knowing what part of the speech the word is (knowing nothing about terminologies and word relations) and thus using it in the wrong way? What if we start to teach learners of foriegn languages the basic relations between words instead of torturing them to memorize just the usage of the word in specific contexts?

Let’s firstly try to recall what semantic relations between words are. Semantic relations are the associations that exist between the meanings of words (semantic relationships at word level), between the meanings of phrases, or between the meanings of sentences (semantic relationships at phrase or sentence level). Let’s look at each of them separately.

Word Level

At word level we differentiate between semantic relations:

• Synonyms — words that have the same (or nearly the same) meaning and belong to the same part of speech, but are spelled differently. E.g. big-large, small-tiny, to begin — to start, etc. Of course, here we need to mention that no 2 words can have the exact same meaning. There are differences in shades of meaning, exaggerated, diminutive nature, etc. 
• Antonyms — semantic relationship that exists between two (or more) words that have opposite meanings. These words belong to the same grammatical category (both are nouns, adjectives, verbs, etc.). They share almost all their semantic features except one. (Fromkin & Rodman, 1998) E.g.
  
• Homonyms — the relationship that exists between two (or more) words which belong to the same grammatical category, have the same spelling, may or may not have the same pronunciation, but have different meanings and origins. E.g. to lie (= to rest) and to lie (= not to tell the truth); When used in a context, they can be misunderstood especially if the person knows only one meaning of the word.

Other semantic relations include hyponymy, polysemy and metonymy which you might want to look into when teaching/learning English as a foreign language.

At Phrase and Sentence Level

Here we are talking about paraphrases, collocations, ambiguity, etc.

• Paraphrase — the expression of the meaning of a word, phrase or sentence using other words, phrases or sentences which have (almost) the same meaning. Here we need to differentiate between lexical and structural paraphrase. E.g.

  Lexical — I am tired = I am exhausted.
  Structural — He gave the book to me = He gave me the book.

• Ambiguity — functionality of having two or more distinct meanings or interpretations. You can read more about its types here.
• Collocations — combinations of two or more words that often occur together in speech and writing. Among the possible combinations are verbs + nouns, adjectives + nouns, adverbs + adjectives, etc. Idiomatic phrases can also sometimes be considered as collocations. E.g. ‘bear with me’, ‘round and about’, ‘salt and pepper’, etc.

So, what does it mean to know a word? 
Knowing a word means knowing all of its semantic relations and usages.

Why is it useful? 
It helps to understand the flow of the language, its possibilities, occurrences, etc.better.

Should it be taught to EFL learners? 
Maybe not in that many details and terminology, but definitely yes if you want your learners to study the language in depth, not just superficially.

How should it be taught?
Not as a separate phenomenon, but together with introducing a new word/phrase, so that students have a chance to create associations and base their understanding on real examples. You can give semantic relations and usages, ask students to look up in the dictionary, brainstorm ideas in pairs and so on.  

Let us know what you do to help your students learn the semantic relations between the words and whether it helps.