同学你好，该知识点来自沪江网校《英语零基础直达大学六级【全额奖学金班】》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~
Last week, a fishman in a bar was explaining to others how he caught a big fish.
fisherman 渔夫

Some time ago, he sailed in near sea to catch fishes.
近海 coastal waters

He known that it was no ordinary fish so he made every effort not to damage it in any way.
known是过去分词，不能作谓语，改成过去式knew
in any way去掉，有made every effort就可以了。

After several hours he pulled the fish up and found that he had never seen it before.
After several hours 最好改成Several hours later
it改成this kind of fish 这种鱼，以前没见过的是这种鱼，而不是这条鱼

He wanted to take it back so that it could be searched by scientists but it got away at last.
search搜索，改成examined考察，调查

祝同学学习进步~