题目内容：

This book will show you ___ can be used in other contexts.
A how you have observed B what you have observed
C that you have observed D how that you have observed
选哪个为什么?

优质解答

选BThis book will show you what you have observed can be used in other contexts.这句话的意思是：这本书将向你展示你观察到的东西如何在其他环境中使用从句中的谓语observe是观察的意思,及物动词,必须跟宾语,但...