It is...that…句式通常不能強調哪些成分

有這樣一道考題：

It was a teacher that she __________.

A. was                        B. seemed                        C. looked                        D. married

此題應選D。從句意上看似乎4個選項都行，其實這里只能填D。因為填A，B，C 中的任意一個選項，都會導致句中的 a teacher成為表語，然而按照強調句句法規則，It is...that這一強調句型是不能強調表語的。一般說來，以下成分不能用于強調句中的被強調部分：

1. 表語：

她很美。

正：She is beautiful.

誤：It is beautiful she is.

他是醫生。

正：He is a doctor.

誤：It is a doctor that he is.

但是賓語補足語卻可以用作被強調部分：

他們選他擔任主席。

正：They elected him chairman.

正：It was chairman that they elected him.

2. since 和 as 引導的原因狀語從句(但 because 從句卻可以)：

他不能來是因為他病了。

正：It is because he is ill that he can’t come.

誤：It is since[as] he’s ill that he can’t come.

3. although 引導的讓步狀語從句：

雖然累了，但他還是去了。

正：He went although he was tired.(www.hz123456.com)

誤：It was although he was tired that he went.