Wait half hour again.

再等半小时。

youdao

Hot water fine. Flip switch. Wait half hour. Take shower. Flip switch off.

热水器好了。开关跳闸，等半个小时，然后冲凉，关掉开关。

youdao

I had to wait half an hour for a bus.

我得等半小时的公共汽车。

《牛津词典》

You have to wait half an hour for that revelation, and it's too late.

BBC: Liar

And yet I often wait for half an hour at peak times cursing taxi cab service in San Francisco.

FORBES: Getting A Job Washing Cars Is Harder Than Getting Into Harvard

In March, more than 300 ambulances had to wait more than half an hour before delivering their patients to hospital staff.

BBC: Royal Cornwall Hospital ambulance waiting crisis 'over'