Helen had left her keys in the office so she had to wait unt

这里要选的时态,主要看she had to wait 的时态,这里用了一般过去时,所以后半句也用一般过去时.同样如果只有后半句的话,也应用came.一般情况下 由until引出的重句,前后都是一般现在时或都一般过去时用的较多,但也可以是前半名是将来时后半句是一般现在时；也可以是前半句是一般现在时,后半句是现在完成时.例1：First write them down in your exercise books, then practice them orally until you have learned all of them by heart.例2：I will stay with you until your lesson begins

因为前面是had left 过去完成时态（过去的过去），所以后面就应该用过去式came
she had to wait until her husband ___home. 也是came

就是选CAME，因为你要分析句子，she had to wait ，，until
你把它啊翻译一下吧她不得不等 直到丈夫回家，HAD是过去式，而用COMES则HAVE要改HAS。所以要一致，
问题补充：是啊