since引导的原因状语从句的例句

He has studied very hard since he came to our school.自从来到我们学校，他学习就非常努力.

Great changes have taken place in our school since you left.自从你离开这里，我们学校发生了很大的变化.

Since you are free today， you had better help me with my mathematics. 既然今天你休息， 你最好帮我补习数学。

since引导的原因状语从句的例句

since引导的原因状语从句翻译成 既然

例如 since you made a mistake， you have to say sorry.