1.Out-of-door____1__a good habit of regular drinking and the avoidance of late eating ___2__are all helpful to sound sleep.（帮忙翻译一下哦，如果能分析一下结构就更好了～～）
1.A.walks B.exercises C.trips D.housework
2.A.worry B.fear C.carelessness D.hard work

2.It is seven years______he left here.(为什么不用完成时呢？）
A.that B.since C.when D.before（改成after可以吗？）

3.Is this factory______he once visited ?
A.that B.which C.the one D.where

（小生不才，麻烦每题都能解释一下，感激不尽的说～～）
实在谢谢各位高手！！！！！！因为本人水平有限请高手详详细细解答

1.你可能漏掉了某些单词。我推测这句的大概意思是：适当的户外运动、好的有规律的饮食习惯和避免过晚进食都有助于深睡眠。
are 之前的应该是主语成分。
2. B It is + 时间段+since+ 一般过去时的句子 =
时间段+has passed+since+ 一般过去时的句子

It is seven years since he left here.=
Seven years has passed since he left here.=
He has been away from here for seven years.=
He has been away from here since seven years ago.
3. C 此题考察定语从句，the one 此时是先行词，此句省略了引导词that。
你将此句换为陈述句语序就可发现
This factory is the one that he once visited .
此句主语是this factory 而非this。