6. On Sundays there were a lot of children playing in the park, _________ parents seated together joking.

A. their                     B. whose                     C. which                    D. that

【陷阱】容易误选B，认为这是非限制性定语从句。

【分析】最佳答案是A。与上面一题相似，their parents seated together joking 不是非限制性定语从句，而是一个独立主格结构，因为空格后的动词 seated 不是谓语，而是一个过去分词，因为 seat 作动词用时，是及物动词。比较以下相似题：

(1) On Sundays there were a lot of children playing in the park, _________ parents were seated together joking.

A. their                      B. whose                    C. which                   D. that

选B。whose parents were seated together joking 为非限制性定语从句，因为其后有完整的谓语 were seated。

(2) On Sundays there were a lot of children playing in the park, and _________ parents were seated together joking.

A. their                      B. whose                    C. which                    D. that

选A。因为句中有并列连词and，整个句子为并列句。(from www.nmet168.com)

(3) On Sundays there were a lot of children playing in the park, _________ parents sitting together joking.

A. their                      B. whose                     C. which                     D. that

选A。their parents sitting together joking 为独立主格结构。

(4) On Sundays there were a lot of children playing in the park, _________ parents sat together joking.

A. their                      B. whose                    C. which                     D. that

选B。whose parents sat together joking 为非限制性定语从句，因为句中有完整的谓语 sat。

(5) On Sundays there were a lot of children playing in the park, _________ parents were sitting together joking.

A. their                      B. whose                    C. which                    D. that

选B。whose parents were sitting together joking 为非限制性定语从句，因为句中有完整的谓语 were sitting。

7. If the man is only interested in your looks, _________ just shows how shallow he is.

A. as                        B. which                       C. what                      D. that

【陷阱】容易误选A或B，误这是非限制性定语从句。

【分析】正确答案为D，注意逗号前是一个条件状语从句，逗号后是该状语从句的主句，that 在此代表前文所述的情况，用作主句的主语。类似地，下面几道题也选 that，而不选 which：

(1) If you promise to go with us, _________ will be OK.

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

(2) If you want a double room, _________ will cost another ￡15.

A. as                        B. which                      C. what                        D. that

(3) Whether you go or not, _________ is quite all right with me.

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

(4) When I say two hours, _________ includes time for eating.

A. as                        B. which                      C. what                        D. that