____ We make         (玩具)in the factory for children from 1 to 5 years old.
____ Mr. Wang enjoys r         newspapers in the morning.
____ He is a police man .It's a             (危险的) job.
____ I think giraffes are good-looking, but lions are u__________ .
____  There is much ________ （雨）here in summer.
____ My mother is l_________ on the beach.
____ What s_________ skirt would Joe like?
____ He is from France. He speaks F________ .  
____ The park near my home is very d_________（脏）, I don't like to go there.
____ There are three            (小偷)in the police station.

 下列物质的用途错误的是（　　）

如图所示，传送带的倾角θ=37°，在电动机的带动下以v=4m/s的速率沿顺时针方向运行，在传送带的底端B有一离传送带很近的挡板P可将传送带上的物块挡住，在传送带的顶端A无初速地释放一物块，它与传送带间的动摩擦因数μ=0.5，A、B间的长度L=9m，物块与挡板碰撞前后物块的速度大小不变，方向相反，物块与挡板的碰撞时间极短．取g=10m/s²，sin37°=0.6，cos37°=0.8．求：