Jack sings better than _____ in his class. Which answer is wrong?

—Mary，new copies of Harry Potter are on sale now． —Great! Let’s go and buy       this afternoon．

Many people have donated that type of blood; however, the blood bank needs ______.

—Do you like __________ here?—Oh,yes.The air,the weather,the way of life.Everything is so nice.

It is not so difficult to learn English well. ________ you need is listening, speaking, reading and writing it every day.