INTRODUCTION - Synonyms
This means using a word which the student knows to get to another of identical or similar meaning. It is perfectly valid for expressions like "CAN" and "ABLE TO", "OUGHT TO" and "SHOULD" (in some of its meanings)
It can be effective but is full of pitfalls for both the teacher and the student. Its single advantage as a technique is its simplicity. Its disadvantages include the fact that, used for an introduction of a word which is not an exact synonym the student will tend to think the two are perfectly interchangeable - and the teacher, may not do enough to bring out the differences. Thus if "MUST" is introduced as a synonym of "TO HAVE TO" (or vice versa) particular attention should be payed to the negative forms which are quite different in meaning.
Another drawback of synonym introductions is that over-use of the technique can easily result in the teacher becoming dependant on it. Infatuated by its apparent facility he will then extend it to introduce words and expressions by relating them to other words which are not really known by the student in English. However, in the students language similar sounding words exist to the English synonym which the teacher wants to use.
Thus a teacher with French students might use:
"ENTER" to introduce "TO GO IN"
It is when he starts using words like "FABRICATE" to introduce "MAKE" that he begins to realise he has gone too far.
The great disadvantage of the technique is, of course, the fact that, having learned that there is a word in English so close to a word in his own language, a learner will make little effort to retain the one which is harder to remember. He ends up using a Latinized version of English quite unlike the spoken language.
Synonyms should thus be used sparingly as an introduction technique.