troubles me most right now is I can’t remember where I have put my car keys.
A. That ;what
B. What;that
C. What;what
D. That;that
网友回答
A. That ;what
(答案→)B. What;that
C. What;what
D. That;that
解析：考查主语从句及表语从句。第一空是主语从句，从句中缺少主语，故用What，第二空是由that,引导的表语从句，句意：现在使我最麻烦的就是我不能记起我把车钥匙放哪里了。所以选B。