21．________ to pass the 2010 college entrance examination made our whole family unhappy.
A．My son failed B．My son's failing
C．My son failing D．My son having failed
答案与解析：B 考查动名词的复合结构作主语的用法。句意：我儿子未能通过2010年大学入学考试，这使得我们全家人不愉快。根据句意和选项可知这里应该用动名词的复合结构，即“名词所有格(或形容词性物主代词)＋动名词”，故选B项。
22．When I was twenty, I had to drop out before graduation and work in a clothes shop to help ________ my family.
A．supply B．support
C．suppose D．stop
答案与解析：B 句意：20岁的时候，我不得不在毕业前退学到一家服装店工作来帮助家里维持生计。support“养活；支持；扶持”；supply“供应”；suppose“假定”；stop“停止”。
