1.it's not good to play tricks on the old.请问这句能这样表达吗:it's no
1.it's not good to play tricks on the old.请问这句能这样表达吗:it's not good to play a trick on
the old把play tricks on 换成了play a trick on
2.after school he goes home alone,同意句 after school he goes home ()().
3.i was doing my homework when my mother ()()昨天妈妈到家时我正在做作业.
4.i ()mum the good news ()()()she ()back .妈妈一回来我就告诉她这个好消息.3,4两句根据汉语意思补全句子