是a better voice还是the better voice

是a better voice还是the better voice
 
请看下面一道题：
How beautifully she sings! I have never heard _________ voice.http://yingyu.chazidian.com
A. a better                        B. a best                        C. the better                        D. the best
【分析】此题容易误选D，认为最高级前用定冠词才是最佳的。其实此题最佳答案为A，该句可视为是下面这句的省略形式：…I have never heard a better voice than her voice. 全句句意为“她唱得多好啊！我从未听过她这么好的声音”。请再看以下类似的实例：
He is fine, never better. 他很好，比以往任何时候都好。
I've never seen a finer bird. 我从未见过比这更美的鸟(即这是我见过的最美的鸟)。
I’ve never found a better job. 这是我找到的最好的工作。
比较以下试题，情形也大致相同：
(1) Boris has brains. In fact, I doubt whether anyone in the class has _________IQ.
A. a high                      B. a higher                       C. the higher                 D. the highest
答案选B，句意为“……我怀疑班上有没有哪个人比他智商更高”，即“我认为他可能是班上智商最高的”。
(2) “Are you satisfied with his answer?” “Not at all. It couldn’t have been _________.”
A. better                        B. worse                        C. more                        D. less
【分析】此题最佳答案为B，关键是要理解 Not at all 的意思。根据上文语境，Not at all 为 I am not satisfied at all with his answer. 之省略，即表示“我对他的回答一点也不满意”，既然如此，他的回答当然会是 couldn’t have been worse（不可能更糟）。