根据上下文,选择适当的词语填空

根据上下文,选择适当的词语填空
We use water 1._____ our homes for drinking,washing,and gardening.We also use it at work and at school.Some factories use a 2.______ of water.And farmers use water to grow our food,too.
Our water 3._____ from a dam in the mountains near the city.It comes to us through pipes.When rainwater 4._____ on the mountains,the dam holds it.
But when there's no rain,no water goes into the dam.As we use more and more water,there is less and less water in the dam.This can be a 5.______ .During the summer,we have very little rain.So please save water .
() 1.A．on B．in C．over D．of
() 2.A．many B．little C．much D．lot
() 3.A．go B．come C．comes D．goes
() 4.A．comes B．falls C．goes D．has
() 5.A．dam B．question C．problem D．water