①Service Provider 电信运营商

　　China Telecom is one of the biggest service providers here in China.

　　中国电信是国内最大的运营商之一。

　　②SIM card 手机卡

　　There's no SIM card in your phone and that's why you can't use the mobile internet.

　　你手机里没有sim卡，这就是为什么你不能上网的原因。

　　③Service plan 服务计划；套餐

　　Some handsets are free when you sign up to certain service plans.

　　当你签约一些套餐的时候，有些手机就是免费的。

　　④roam /ro?m/ v. 漫游

　　On my vacation I didn't realize that my phone was roaming. I paid a lot of money for each call.

　　度假时我没意识到手机是在漫游，所以每个电话都花了好多钱。

　　⑤coverage (信号)覆盖

　　Which service provider has a better coverage, China Telecom or China Mobile?

　　哪个运营商的信号更好呢，中国电信还是中国移动？

　　⑥top up 充值

　　I need to go to the shop and top up my mobile phone.

　　我得去商店给我的手机充下值。

　　out of data/minutes 没流量了/没话费了

　　I am out of data.