For some time the expert __________ people of the health risks caused by passive smoking. He says he won’t stop until all the smokers around him decide to quit smoking.
Although the first part of the book is easy, the rest ______.
----Where are you now? ----Well, I have arrived at _______ is called “the West lake”.
If you want to improve your oral English, you’ll first have to _______yourself of those shortcomings.
It was ________ he came back from Africa that year _________ he met the girl he would like to marry.
Though the professor tried his best to explain the difficult question, the students still looked _____.