同学你好，该知识点来自沪江网校《新概念英语1、2、3、4册连读【学霸班】》的课程，想要更系统的学习，欢迎进入课程学习。不仅可以和更多的同学一起学习，而且还有老师、助教随时的学习指导和知识点解答哦。

同学你好^_^

现在完成时Since he hasn't arrived yet, 一般将来时he will be unlikely to come now.
既然他还没有到，他这会儿不大可能来了。

yet 用于否定句，表示“还未”

now   【副词】这么一来
•
Having met the rest of the family, she now saw where he got his temper from.
见到他家里的其他人之后，她这才明白他的脾气是从哪儿来的。
•  
Mrs. Chandra has received one sweater for each of her five children and says that the winter will not be so hard now.
钱德拉太太已经收到了发给她5个孩子每人一件的毛衫，并且说这样一来冬天就不会那么难过了。
•  
She told me not to repeat it, but now I don't suppose it matters.
她告诉我不要重复它，但是这样一来我认为它不重要了。

yet   【副词】尚 (用于否定句); 已经 (用于疑问句)
•
They haven't finished yet.
他们还没有结束。
•  
No decision has yet been made.
尚未作出决定。
•  
She hasn't yet set a date for her marriage.
她尚未定下她结婚的日子。

希望以上内容可以帮助到同学，祝学习愉快~

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