A:put off it
B:put it off
C:fixed up it
D:fixed it up
-- Do you want to play_____ tennis with me?
-- Yes, I ___________.
我国的地势特点是( )
先观察下列的计算,再完成习题:
12+1=(2−1)(2+1)(2−1)=2−1 ;
13+2=3−2(3+2)(3−2)=3−2
14+3=(4−3)(4+3)(4−3)=4−3
请你直接写出下面的结果: