She looks sad. Could you please tell me that prevents her from being as happy as
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She looks sad. Could you please tell me ____ that prevents her from being as happy as before?
A. what it is B. it is what C. how it is D. it is how
试题答案
A
解析:
本题含有强调句型，若把It is……that去掉，则很容易地看出what引导的宾语从句，what在从句中充当主语。故选A。