1、She didn't go to bed until she had finished her work.她直到把工作做完之后才睡觉。
2、I have owned a puppy before.我以前养过一只小狗。
3、How long have you been working in this library?你在这家图书馆工作多久了?
4、She has been teaching in this school for ten years.她在这所学校教书已经10年了。
5、Hardly had I reached the school when the bell rang.我一到学校,铃就响了。