We all feel after hearing of the news.

Both the young and the old are getting crazy _______ WeChat(微信).— I agree. Nowadays we can see many people spend their free time ______ it.

I can’t stand action movies because they are .

Not until he failed in the last examination _________he should have spent more time on study.

Though he failed in the experiment again and again, he didn’t______, and at last, he made it.