根据短文内容，选择正确答案。 My friend Bob has an interesting hobby. He likes collecting stamps. He spends a lot of time on his stamp collection after school hours. Now he has hundreds of stamps from all over the world. Bob likes stamps with pictures of animals and plants on them. In this way, he learns the names of many animals and plants. He also borrows books on animals and plants from his school library. He learns a lot from them. Sometimes Bob has many stamps of the same kind. He gives some of them to his friends. And they give him others in return (回报). Bob often writes to his friends in many countries. He sends them stamps of his country. In return, they send him stamps of their countries. Bob thinks collecting stamps can bring him much knowledge, pleasure and happiness. And he can make more friends from all over the world.1. Bob spend a lot of time on his hobby ______.A. during his holidayB. after school hoursC. during school hoursD. on Sundays 2. Bob learns a lot about animals and plants from ______.A. his teachersB. his friendsC. his stamps D. his classmates3. When Bob has stamps of the same kind, he ______.A. sells them to his friendsB. throws then awayC. keeps them for himselfD. sends some of them to his friends4. Bob often sends some stamps to his friends in many countries, and the friends ______.A. send him other stamps in returnB. write him letters for thanksC. give him some moneyD. send him some foreign coins5. Collecting stamps can make Bob ______.A. very happyB. learn much knowledgeC. make more friendsD. A, B and C