答案:B
选词填空。
1. What would you like (with, for) breakfast?
2. I'd like some cabbages (and, or) eggplants.
3. The fish (is, are) too salty.
4. I (can, would) like some carrots.
5. What do you (have, has) for lunch?
如图所示,质量为M的斜劈形物体放在水平地面上,质量为m的粗糖物块以某一初速度沿劈的斜面向上滑,至速度为零后又加速返回,而物体M始终保持静止,则在物块m上、下滑动的整个过程中( )
A.地面对物体M的摩擦力先向左后向右
B.地面对物体M的摩擦力方向没有改变
C.地面对物体M的支持力总小于(M+m)g
D.物块m上、下滑动时的加速度大小相同