下列句子中均有一处错误,请找出并在后面的横线上改正.要答案还有哪里错了?

题目

下列句子中均有一处错误,请找出并在后面的横线上改正.要答案还有哪里错了?
1.Cathy can't go to school alone,because her is too young.__________
2.Can you pass the salt to I can't reach it.__________
3.Ben made a cake by him yesterday.__________
4.when you finish reading the books.please put they back on the shelf.__________
5.kids,help yourself to the sweets!__________

答案

1.Cathy can't go to school alone,because her is too young.————her--->she
2.Can you pass the salt to I can't reach it.———— I -->me(是第一个I)
3.Ben made a cake by him yesterday.————him-->himself
4.when you finish reading the books.please put they back on the shelf.
————they-->them
5.kids,help yourself to the sweets!————yourself-->yourselves