He is good at reading and writing, but he wishes he knew how to understand and speak better.
他的阅读和写作是强项,但他希望知道怎样去理解和说得更好。
and it is only in the seas and rivers, and sometimes lakes, where mud and sit have been continuously deposited,
所以只有在泥沙不停淤积的海洋和江河里,有时在湖泊里,