完成句子。

________(在很多情况下)，this kind of matter is hard to deal with．

I hadn't waited long ________ she came．

Someone called me up in the middle of the night, but they hung up ________ I could answer the phone．

辨析：join; join in; attend; take part in; go in for; enter for; be present at

1)Our headmaster will ________ us ________ the discussion this afternoon．

2)They had a quiet wedding－only a few friends ________(it)．

3)We'll ________ social activities during the summer vacation．

4)Jack has ________ the long jump, but I don't think he has a chance to win．

5)A lot of people ________ the medical conference in London last month．

用join的适当形式填空。

________ the union/club/army/police, etc

用join的适当形式填空。

Membership is free, so ________ today!

用sure＆certain的适当形式填空。

She will not come here for ________ reason．

用sure＆certain的适当形式填空。

I am ________ that he will win the race．

用sure＆certain的适当形式填空。

It is ________ that the earth is round．

Mary will be here ________(确定地)in half an hour．