at what time will he 为什么前面要加个at

问题描述:

at what time will he 为什么前面要加个at
不加at 又成什么了

什么时候他将离开.at what time=when
表示“在.时候(几点)”用"at."
eg.I get up at 6:00 every day .
He often goes to school at 7:00 in the morning.