充话费英文怎么说？

　　top up 充值

　　My phone is out of credit，I have to top up it .

　　我手机没钱了，得去给手机充值。

　　I don’t have any money on my phone. I have to put 100 yuan on it.

　　我手机没钱了，得去给手机充100元。

　　疯狂练习吧！