这是一篇短文改错题，一共有十处错误，请帮我找出来，谢谢

1.share--to share (want to do sth.固定搭配）
2.them--it （指代a chocolate cake, 用单数it)
3.在find后加上it下班（find后缺少宾语，故加it，指代a chocolate cake)
4.eats--ate （过去行为用过去式）
5.other--others （others “别人”，可以单独使用；other “别的，其他的”，不能单独使用）
6.busy前的is--was （他过去很忙，故用过去式）
7.angrily--angry ( 做宾补，用形容词：make sb.+adj.)
8.去掉on以轻心 （one night前不加介词）
9.loudly--loud (做定语，修饰music, 用形容词）
10.在4 o'clock前加上at （在时刻前用at）
11.difference--different (作表语，用形容词）

My brother Tom was very selfish when he was a little boy. He didn't want (加上to)share things with other people.For example,when he bought a chocolate cake, he put them(them-it) in a secret place where Icouldn't find.then he eats (eats-ate)itall by himself.He never helped other(other-others).He said he is(is-was) busy.That is,a game of tennis making him very busy.He didn't care if something (something-anything)he did made people angrily(angrily-angry).For instance,on (on去掉)one night he played strong and loudly(loudly-loud) music still 4 o'clock in the morning.But he is difference(difference-different) now.He often helps Grandma with housework ,Mom with cooking and his classmates with their lessons.