Some of these studies (have shown) that although some people have trouble (to fall asleep), others have an (equally) difficult t

admin2011-06-29  45

问题 Some of these studies (have shown) that although some people have trouble (to fall asleep), others have an (equally) difficult time (waking up).

选项 A、have shown
B、to fall asleep
C、equally
D、waking up

答案B应改为falling asleep。

解析 have trouble doing sth.
转载请注明原文地址:https://jikaoti.com/ti/sA5YFFFM
0

最新回复(0)