This book will show you______can be used in other contexts.A.how you have observed at you have observedC.how what you have observedD.how that you have obseved为什么要选C，A怎么不对了？？？
热心网友
要是A的话，那么充当how引导的从句里面就少了宾语应该是sth (you have observed) can be used，而不是you have observed can be used
热心网友
用A的话，应改为 ....how sth you have observed can....用语法解释实在很枯燥，建议多读课文，加强语感，就能轻松解决