①.already 和yet都可作“已经”讲,already主要用于肯定句中,常与完成时连用,也可用于一般过去时(此时动词必须是持续性的);如果是系表结构的句子,也 可用于一般现在时。already也可用于疑问句,表示期望得到肯定的回答或表示惊异,此时already常放在句末。而yet通常与一般现在时或现在完 成时连用,常用在疑问句中。 如: i have already seen the film.我已经看过这部电影了。i already know about it.我已知道此事。she's here already,she's early.她已经到了,她来得很早。 has she found her bike already?她已经找到自行车了? have you found your ruler yet?你已经找到尺子了吗?is supper ready yet?晚饭准备好了吗? ②.still 和yet都有“还”、“仍然”之意,still表示“某事尚在进行中”,常用于肯定句中,也可用在疑问句或否定句中,在否定句中须放在否定词not之前。 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: they were still neck and neck.他们还是齐头并进。does he still work in the factory?他还在那个工厂工作吗? they still haven't got more money.他们直到现在还是没有得到更多的钱。he has not yet begun to work.他尚未开始工作。—have you had your lunch?你吃过中饭了吗?—no,not yet.还没有。