It’s time that we _____ to take care of our own house.
It’s time that we \_\_\_\__ to take care of our own house.
表示
Since this road is wet and slippery this morning, it _____ last night.
Since this road is wet and slippery this morning, it \_\_\_\__ last night.
如图5所示，在光滑的水平面上，一质量为mＡ＝0.1千克的小球A，以8米/秒的初速度向右运动，与质量为mＢ＝0.2千克的静止小球B发生正碰．碰后小球B滑向与水平面相切、半径为R＝0.5米的竖直放置的光滑半圆形轨道MN，且恰好能通过最高点N后水平抛出．求： （1）碰撞后瞬间小球B的速度大小； （2）小球B从轨道最低点M运动到最高点N的过程中所受合外力的冲量； （3）碰撞过程中AB组成的系统损失的机械能．图5
如图5所示，在光滑的水平面上，一质量为mＡ＝0.1千克的小球A，以8米/秒的初速度向右运动，与质量为mＢ＝0.2千克的静止小球B发生正碰．碰后小球B滑向与水平面相切、半径为R＝0.5米的竖直放置的光滑半圆形轨道MN，且恰好能通过最高点N后水平抛出．求： （1）碰撞后瞬间小球B的速度大小； （2）小球B从轨道最低点M运动到最高点N的过程中所受合外力的冲量； （3）碰撞过程中AB组成的系统损失的
By the end of the next month, you _____ here for three years.
By the end of the next month, you \_\_\_\__ here for three years.
_____ succeed in doing anything.
\_\_\_\__ succeed in doing anything.
—Tom, is there _____ wrong with the car?—Yeah, the engine refuses to start.
—Tom, is there \_\_\_\__ wrong with the car?—Yeah, the engine refuses to start.
I know you’re planning to travel this summer, but do you know _____?
I know you’re planning to travel this summer, but do you know \_\_\_\__?
We have always thought very _____ of him.
We have always thought very \_\_\_\__ of him.
During the past ten years, there have been _____ changes in the country.
During the past ten years, there have been \_\_\_\__ changes in the country.
I have promised to help you and I’ll _____ my word.
I have promised to help you and I’ll \_\_\_\__ my word.