7. An early American film star，Pearl White starred in several serials whose episodes had suspenseful endings that enticed audiences to return for the next installment.

　　(A) serials whose episodes had suspenseful endings

　　(B) serials，their episodes had suspenseful endings

　　(C) serials，which had episodes ending suspenseful

　　(D) serials of whose episodes the suspenseful endings

　　(E) serials，each of these episodes had a suspenseful ending

　　答案：A

　　类型：定语从句

　　解析：serials之后的内容是来修饰serials的。A选项whose引导定语从句，划线部分之后的that指代的是endings。B选项是典型的run-on句子，两个完整的句子之间没有连词，也不构成主从复合句，B错。C选项错在ending suspenseful，end在这里是动词，那么suspenseful应该使用副词形式。D选项是定语从句使用错误，whose引导的定语从句不用再加of了。E也是run-on句子。

　　8. Although we typically associate deserts with hot，dry wether，deserts can also be cold，most of Antarctica is a desert despite the continent's frigid temperatures.

　　(A) cold，most of Antarctica is

　　(B) cold;most of Antarctica is

　　(C) cold，in fact，most of Antarctica is

　　(D) cold;whereas most of Antarctica is

　　(E) cold，such as most of Antarctica being

　　答案：B

　　类型：句子结构

　　解析：原句是典型的run-on，两个完整句子之间没有连词，也不构成主从复合句。C与A选项错误类型一样，都是run-on。D选项首先用了分号，分号之后应该是完整的句子，whereas是连词，所以后面部分不是完整句子。E中being不简洁。