7:30用英语有三种表达方法:half past seven;seven thirty;7:30 p.m.
例句:Classes start at half past seven.
七点半钟开始上课。

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He signed on at half past seven.
他于七点半签到上班。
Let's meet at half past seven.
让我们七点半见面吧!
Let's set at half past seven.
让我们定在七点半吧。
Ms Smart: Half past seven.
斯玛特女士:七点半。
I eat breakfast at half past seven.
我七点半吃早餐。
My mobile phone says half past seven.
我的手机显示:七点半。