A:13
B:3
C:-3
D:−13
A: What are you doing?(你们在做什么?)
B: We is playing. ____
A: You's big. ____
B: Now we'are small. ____
A: Are you happy?
B: No, we are. ____
A:Are you celd? ____
B: Yes, we are hot.
选择合适的词语填空。
x+____=57+x