—How's your new babysitter?
—We ask for a better one.All our kids love her so much.(2011·浙江)
A. should
B. might
C. mustn't
D. couldn't
网友回答
A. should
B. might
C. mustn't
(答案→)D. couldn't
解析：考查情态动词的用法。句意：——你的新保姆怎么样？——找不到更好的了。我们的孩子们很喜欢她。should应该；might可能，可以；mustn't禁止；couldn't不可能。根据句意选D。