A:温度升高,内能增大
B:温度降低,内能减小
C:温度不变,内能不变
D:温度降低,内能增大
选出最佳应答语。
A.It's 9 o'clock.
B.It's sunny.
C.Yes,we do.
D.It's on the first floor.
E.No,it isn't.
This is my .