在过去几年里我们培训的老师和学生中都普遍不喜欢使用强调句，尽管大家在中学阶段就已经学习过这个知识点。其次是强调句用it引导时后面的连接词到底是该用that呢还是其它的例如who, when, where。
Cleft sentences (It was in June we got married.)
We use cleft sentences, especially in speaking, to connect what is already understood to what is new to the listener. In a cleft sentence, a single message is divided (cleft) into two clauses. This allows us to focus on the new information.
It-cleft sentences
It-clauses are the most common type of cleft clause. The information that comes after it is emphasised for the listener. The clause which follows the it-clause is connected using that and it contains information that is already understood. We often omit that in informal situations when it is the object of the verb:
. A: Sharon’s car got broken into yesterday, did it?
. B: No. It was Nina’s car that got broken into!
Focus (new information): it was Nina’s car Understood already (old information): a car got broken into
. A: You’ve met my mother, haven’t you?
. B: No, it was your sister (that) I met!
Focus (new information): it was your sister
Understood already (old information): I met someone in your family
Is it August that you are going on holiday?
Focus (new information): the month August?
Understood already (old information): you are going on holiday
When a personal subject is the focus, we can use who instead of that. We often omit who in informal situations when it is the object of the verb:
It was my husband who (or that) you spoke to on the phone. (or It was my husband you spoke to on the phone.)
When a plural subject is the focus, we use a plural verb but It + be remains singular:
It’s the parents who were protesting most.
We can use negative structures in the it-clause:
It wasn’t the Greek student who phoned.
Wh-cleft sentences (What I need is a holiday)
Wh-cleft sentences are most often introduced by what, but we can also use why, where, how, etc. The information in the wh-clause is typically old or understood information, while the information in the following clause is new and in focus:
. A: I don’t know what to cook for them? I don’t know what they like.
. B: What they like is smoked salmon.
Understood already (old information): we are talking about what they like to eat
Focus (new information): they like smoked salmon
. A: This remote control isn’t working.
. B: What we need to do is get new batteries for it.
Understood already (old information): there is something that we need to do to fix the remote control.
Focus (new information): we need to buy new batteries