____you know English is very important,you should learn it well.
A.For B.Since C.Because D.Because of
选项D肯定不正确,关键是A、B、C如何选择,三个都有因为的意思,都能说得通.我个人偏向选B,既然,但不知正确与否,或为什么排出其它选项.