The journey to the airport takes about half an hour.

　　到機(jī)場大約需要半小時。

　　After half an hour, the fish stopped biting and we moved on.

　　過了半小時，魚不再上鉤，我們就走開了。

　　I could stuff myself with ten chocolate bars and half an hour later eat a big meal.

　　我可以給自己塞下10塊巧克力，并在半小時后再大吃一頓。