hi. you took note so careful[emoji] but I had a question after reading your notes 我的水平没有退步了。 do you mean your level is dropped before but now the dropping period is stoped? cause in Chinese, normally, 没/没有 can not use together with 了 （没，didn't do sth; 了, did sth，they are conflict） only one situation is exceptional. that 了 put at the end of a sentence and means a new situation is happening. like 我没吃晚饭。（I didn't have dinner ） 我没吃晚饭了。（maybe I had dinner one minute ago but now I stoped this action） 我没有书。（I don't have a book） 我没有书了。（now I don't have books maybe I had before but now sending to others or selled[emoji]） so, if you just wanna tell us that your level hasn't been dropped, you'd better say 我的水平没有退步。 hope this will be helpful[emoji]

My pleasure!

Thanks!

我的词汇量比较少 - My vocabulary is small. 不用比较级 投资 invest investment, 投资者, 投资人 investor