为什么是What's the best time to go there?而引导词不是When?

为什么是What's the best time to go there?而引导词不是When? What animal keeps the best time?为什么是watch What's the best movie theater? What's the best movie theater? you know mp3,what's the best What’s the best and cheapest light? best way,what's the meaning? What's the best and cheapest light? what's the best restaurant什么意思 What's the best song in 2011 what“s the writers opinion on the best what“s the writers opinion on the best part? What's on the desk?------There're some model planes on it.为什么是What's 不是What're. 英语翻译What's the best gift you have ever received? What's the best way to get there?翻译下 What's the best title of this passage? what s the best clothing store in town 翻译 What's the best movie theater? 什么意思啊?