A． windB． snowC． airD． rain

A．It is about to start raining.B．The rain will stop soon.C．It has been r

He usually goes to beijing by （).A.an airB.airC.the airD. airing

If it ______tomorrow, the sports meeting _____put off.A、rains, isB、rains, will beC、will

How many centimeters of rain have fallen within a day during the heavy rain？A．10.B．24.C．28

首先将钠石灰用于麻醉的是（)A.RovenstineB.SnowC.LavoisierD.JiuporobE.Guedel

Acid rain is a form. of air pollution currently