[英文] after 一問

after可以咁解
在...以後,
在...後面;隨...之後

1 After graduation he went abroad.
畢業後他去了國外。
2 At half after ten it began to rain.
在十點半下起雨來。

我唔明第1-2句點解會咁解 after唔係解係 在..後面? 第2句個after 唔係應該放係最前？？ After at half ten it began to rain 在10點30分後下起雨來