Mr. Black has been teaching English in a middle school _____ he came to China.

Put yourself in situations where you have to communicate in English, _________ you’ll make progress over time.

He is unusually warm-hearted, loving and generous, _______all his friends can see.

The most exciting thing for him was _________ he finally succeeded in _________ seemed to be a difficult exam to him.

Scientists say it may be five or six years _______ it is possible to test this medicine on human patients.

---When did you get to know each other ?
----It was in 2008___      we spent summer vocation together.

Everyone wants to be a friend of _______________ is considerate and shares the same interests.

--- Jason, have you finished your writing?
---Five more minutes________ you will see an amusing story!

Our new science teacher comes from either New York or Washington. But I can’t remember _______.

The police set about arresting the suspect ______ they found enough evidence to prove him guilty.