2-- Well, I wouldn't swim in it- but the water is much cleaner than it was a few years ago.
 
1-- Are local factories allowed to discharge waste water into the lake?
 
2-- Yes, but it must be treated in an effluent treatment plant first.
 
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注解：
 
1.polluted污染
2.local factories当地工厂
3.treatment处理

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译文：

1--这个湖污染严重吗？
2--哦，我没法在里面游泳，但是比前几年清洁多了。
1--允许当地工厂把废水直接排放到湖中吗？
2--是,但是废水必须首先进入污水处理厂处理。