根据句意选择合适的单词填空。
1. The bus is __________ (quick, quickly). It goes __________ (quick, quickly).
2. The snail is __________ (slow, slowly). It goes __________ (slow, slowly).
3. The lion is __________ (quick, quickly). It is running __________ (quick, quickly).
4. The boy walks __________ (slow, slowly). He is __________ (slow, slowly).
5. The plane is flying __________ (quick, quickly) now. It is __________ (quick, quickly).
