yet和already的用法及区别

already和yet都可作“已经”讲
already一般用在完成时态的肯定句中.
Have you found your ruler yet?你已经找到尺子了吗?
I have already seen the film．我已经看过这部电影了.
We have already read the book.我们已看过这本书.
already若用在疑问句中,常表示吃惊意外的语气.此时already常放在句末.
如：Have you had your lunch already?)
Have you finished already?(我以为你没有做完,表示出乎意料.)
Well,have you forgotten already?Two weeks ago,it had a baby.
yet一般用在完成时态的否定句和疑问句中.
Have you found your ruler yet?你已经找到尺子了吗?
yet表示“某事尚未发生或完成”,多用于否定句或带否定词的陈述句中.如
Does he still work in the factory?他还在那个工厂工作吗?