關於一句英文句子問題。?

我懷疑這句話的意思是＂隔天早上＂而不是＂明天早上＂．也就是，與說話的時間是＜相對的＞＜隔天＞而不是＜一月３１日２０２１年＞的＜明天（未來）＞

而且說這句話的人應該不是說英語的人．一般，說英語的人都不會犯到醬子的錯誤．

所以，你的原句應該寫成：

Since my sister had to take the train early next morning, Mom told her not to sleep late.
但是．．．
語言本來就是＂語意＂重過文法，在英語是第二語言，外來文化習慣（混用next morning 與tomorrow morning）越來越被接受的狀況下，這種說法可能越來越多．醬子，你就要用上下文來分辨作者的時間座標用意是＜相對＞還是＜絕對＞的？

> Since my sister ... the train early in the morning,…嗎?
要是姊姊＂每天都坐早班車＂而不是＂只有隔天＂，那就應該用簡單式：
Since my sis has to take the train early in the morning, mom tells (or told) her sleep early.

Mom told her not to sleep late---->(main clause)
Since my sister had to take the train early in the (next)morning------>(subordinating adv.clause of reason, manner)
have to do something
=have to
=has to
=had to
=expressing obligation or necessity;-
eg:-Do your sister often have to go to the train early ?
-----She doesn't have to go early, No !?
-----She doesn't go late.
-----She had to be getting along early !!!!!The sentence means----
=She had to leave early
=She HAD TO leave early(----------)
考試考義務责任=obligation=HAD TO
(20 marks demanded)