其实作为一个高中生你的作文写得相当有水平. 我就提几点吧, 首先你可以用notorious代替well-known, 表示臭名昭著的.
其次, 第三行的selfish是形容词, 应该改为名词形式selfishness或者selfish behaviour 自私行为.
再就是, 第二句, to everyone's surprise, the teacher should have left all his students...这句话你用了should have left, 在这里表示虚拟语气. 翻译成中文就是, 他本应该丢下他的学生...这就与你要表达的意思相悖了. 建议你直接用left.
然后就是, not only...but also...那里, but also 后面应该再跟一个have, 然后接宾语, 或者你可以改成a qualified teacher should have not only a goodcommand of teaching, but also an enthusiastic attitude to all his beloved students.
not only和but also 后跟的成分一定要对等
另外就是我觉得你的should... 应该怎么怎么样用得多了点, 会引起一点视觉疲乏.
其实你可以变换一个句型
比如in my opinion那段, 你前面用了一个should... 后面的句子可以改为
It's very important 或者 it's of great importance for him to be responsible for all the students he teaches and regards them as his own children.
what's more后面那句话我觉得再添加点东西更好, 老师应该和蔼可亲, 能够原谅他犯错的学生(并且让他明白他错在哪)而不是立马惩罚他.
He should be amiable and forgive his student who has made mistakes and let him understand wherein he's mistaken instead of...
mistaken在这里作形容词, 表示错了
另外我觉得forgive前的can可以去掉
forgive与be 共用一个情态动词should 应该
最后, he should be an honest person. 他应该是个诚实的人. 我觉得我会用has to be强调一下, 他得是个诚实的人.
你的文章很不错, 真的很不错, 说实话, 我都不能保证我能写得像你这么好, 这些只是个人愚见.