Some people seem too think its for practicing grammar rules and learning lists of words.
一些人认为它是用来操练语法规则和学习一大堆单词。
Once bit, twice shy.
一朝被蛇咬,三年怕草绳。
As far as I could see, it needed only a minor adjustment: a turn of a screw here, a little tightening up there, a drop of oil and it would be as good as new.