限制性定語從句還是非限制性定語從句

下面這道題是考查限制性定語從句還是非限制性定語從句?

If a book is in English, __________ may mean slow progress for you.

A. that                        B. which                        C. as                        D. and it

此題應選 A。容易誤選 B。許多考生一看到空格前的逗號，就想當然地認為這是非限制性定語從句，從而誤選了B。

考生可以想一想，假若此題選B(which)，which 用以引導一個非限制性定語從句，而其前又是一個以if 引導的條件狀語從句，那么請問：此句的主句在哪里?

通過以上分析我們可以知道，既然本句前面有一個條件狀語從句，那么后面一句就應該是主句。本題選that, 即為主句主語，全句意為：如果一本書是用英語寫的，那么那就意味著你要讀得慢些。

注意：當從句位于主句之前時，千萬不要在主句前誤加并列連詞或誤認為是某種從句。請做以下單選題。如：

1. When he was tired, ________ he had a rest.

A. and                         B. but                     C. so                           D. ×

2. Because he got up too late, ________ he missed the train.

A. so                           B. but                      C. and                        D. ×

3. Though he is poor, ________ he is happy.

A. and                         B. so                       C. but                         D. ×

5. As is known to us all, ________ China was liberated in 1949.

A. and                         B. but                      C. which                    D. ×

答案：1. D 2. D 3. D 4. D 5. D