2--It's certainly a big improvement over yesterday.
 
1--But it's supposed to get cloudy and windy again this afternoon.
 
2--Well, the worst of the winter should be over.
 
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注解：
 
1.certainly肯定      
2.improvement改善 
3.supposed据说   

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译文：
 
1--我想今天会是一个好天。
2--肯定比昨天大有好转。
1--但是，据说今天下午又要转阴而且刮风了。
2--不过，冬天最糟糕的一段日子总该过去了。