—I hear Robert has gone to Harvard Unive

若⊙O₁的半径为3，⊙O₂的半径为1，且圆心距O₁O₂=4，则⊙O₁与⊙O₂的位置的关系是[ ]

A.内含

B.内切

C.相交

D.外切

It is reported that Beijing and Zhangjiakou（张家口）will compete to host the 2022 Winter Olympics, which will _____ China’s social development.

A．interest

B．benefit

C．gain

D．contain

Last weekend I had       homework. After finishing it, I felt        tired.

A．too many, too much

B．too much, much too

C．much too, too much

D．much too , much too

治疗肺热燥咳宜选用（）

A.半夏

B.桑白皮

C.枇杷叶

D.牛蒡子

E.桑叶

在使用防冻液过程中需要注意哪些方面？