This kind of medicine has a bad ________on our brains.
Failure can make a positive contribution to your life______you leam to use it.
The police have issued a detailed______of the missing boy.
-Did you receive my letter? -I received one just as I______
The quick rise in the price of food will make people______,that is,offect people's living standard.
-I can't get on well with some of my classmates. They just leave me in the cold. -______But what's the reason?