几时 即什么时候 用when
如: When will you go to Beijing?
你什么时候去北京?
几点, 用 what time
What time will you arrive in Beijing? At about ten o'clock.
你几点到北京? 大约10点钟.
几号 用what date
如: What date will you arrive in Beijing? On July the 1st.
你几号到北京?大约7月1日.
星期几 用what day
如: what day is today?今天星期几?
It's Tuesday.今天星期二.
如果什么都不知道,所有都要问的话,那就是用when 我给你天书号 看图