两个滑轮完全相同，其重力均为20N．分别用如下图所示的两种方式，将重400N的物体以相同的速度匀速提升了10m，不计摩擦和绳重，则下列判断正确的是（）

    Mary works in a bank. She is ____ busy every day that she____ no time to make dinner. There is a(n)____near Mary's house. After Mary comes back home from work, she likes to go to the restaurant____dinner.

    One day,____ Mary was in the restaurant, she saw____old man next to her looking for (寻找)something on the floor(地板).Mary felt surprised. So she____the old man.

    "____are you looking for?"

    "Oh, a piece(块)of bread," the man answered.

    "A piece of bread? Oh, the floor is so____.Please take this piece." Mary gave(给)a big piece of bread to the old man.

    "But my teeth____in that piece of bread."

英国的汤姆、沙特阿拉伯的穆罕默德和泰国的阿里，在一次旅游时乘上了同一架飞机。他们分别使用不同的语言，信仰不同的宗教。结合下图回答(1)～(3)题。