"Since" 是一个常用的词，可以表示"自从"，"因为"，"既然"等不同的意思。在英语中，"since" 也可以用来表示连续的时间段。
以下是一些常见的"since" 的用法及短语：
-
"Since" 表示"自从"，后接一般过去时或者现在完成时。
- I haven't seen him since yesterday. (自从昨天之后我就没见过他了。)
- She has been studying English since she was in primary school. (她从小学开始就一直在学英语。)
-
"Since" 表示"因为"，通常在句子中作为原因状语。
- Since he is sick, he cannot come to the party. (因为他生病了，所以不能来参加聚会。)
- Since you are not interested, we won't force you to come. (既然你不感兴趣，我们就不强迫你来了。)
-
"Since" 表示"既然"，通常用于表达建议或者提醒。
- Since you have some free time, why not come and visit us? (既然你有些空闲时间，为什么不来看看我们呢？)
- Since you are going to the supermarket, can you please buy some milk for me? (既然你要去超市，能不能帮我买点牛奶？)
-
"Since" 表示"自从…以来"，通常后接一段时间，用来表示从某个时间点开始一直延续到现在的时间段。
- I have been living in this city since 2010. (我自从2010年以来一直住在这个城市。)
- He has been working for this company since he graduated from college. (他自大学毕业以来就一直在这家公司工作。)
总之，"since" 在英语中是一个常用的词汇，有多种不同的用法和短语，掌握这些用法可以帮助我们更好地理解英语语言的表达和交流。
