AIDS is said _______ the biggest health challenge to both men and women in that area over the past few years.
Did you ask whose computer ______________ ?
If you ____ your money ____ mine, we will have enough to buy one more set of stamps to ____our collection.
It was only with the help of the local guide ______.
---Is this book interesting? ---Yes, but I’m sure it won’t interest __________.
We should consider what use can be made ______ such a material(材料).