在英语中,since常用作原因状语从句,用来表达因果关系,表示某个事件或情况的起因。在句子中,since通常放在句首,后面跟一个完整的从句。
例如:
- Since it's raining outside, we should bring an umbrella.(因为外面下雨了,我们应该带一把伞。)
- Since she started studying English, her grades have improved.(自从她开始学习英语,她的成绩有所提高。)
- Since I don't have a car, I have to take the bus.(因为我没有车,所以我得坐公交。)
需要注意的是,since还有一个常见的用法,即表示“自从……以来”,此时后面的从句应该用现在完成时态。例如:
- Since I have been living in this city, I have made many new friends.(自从我来到这个城市,我交了很多新朋友。)
- Since they have been married, they have traveled to many different countries.(自从他们结婚以来,他们去过很多不同的国家。)
总之,since原因状语从句可以让句子更加连贯,更加清晰地表达出因果关系。我们在写作和口语中,可以灵活使用since,使语言更加地丰富多彩。