自从以后

The children are completely out of control since their father left.

I haven't seen him since the summer before last.

从…以来

It's been an age since we've met.

She's been using drugs since she was 13.

自从

Since when have you been working here？

Since when do you think you're in charge？

因为

Since you're here, let's start the meeting.

Since you're feeling unwell, let's call off the trip.

这些例句展示了"since"在不同语境下的用法，包括引导时间状语从句、表示从某个时间点开始到现在的时间段，以及作为连词或介词表示原因。希望这些例句对你有所帮助。