on school night为什么不加a如上,请详解on school night 为什么不像on a beautiful day一样加a,尽快呀,(或者是on school nights)另外补充：1.on Sunday和on Sundays 分别在什么情况下用,详解区别,如例句：Be at home on

on school night为什么不加a如上,请详解on school night 为什么不像on a beautiful day一样加a,尽快呀,(或者是on school nights)另外补充：1.on Sunday和on Sundays 分别在什么情况下用,详解区别,如例句：Be at home on where did you do last night,last night前为什么不加on on school night有at night为什么不是at school night 具体说明原因~ at night不是在晚上吗,为什么on school night却用的是on呢? I eat fruit 为什么 fruit不加SHere are the results of the student at green high school中得 the student 为什么不加S?I sleep every night中得 night为什么不加S?是Here are the results of the student activity survey at green high school Don't go out on school night,____ you?为什么用will?用do行吗?为什么? on school night还是nights on school day还是days 为什么On school nights,Nights要复数?the whole night就不用 i can not sleep the night 这里的night为什么不加s? Do you want to go out with me Friday evening?为什么Friday evening前面不加on?对不起，请把evening改成night~ night什么时候用介词on什么时候用at比如at night ,on school night,on a cold night night能不能用介词on?比如：on the night Bob watched TV last night.为什么不加s加ed? how far from school she lives.为什么不加to? 为什么the school life of American students.后面不加“ ’? 为什么English前面加in而不加on 英语中直接引语中的on Friday night 改为间接引语时,需要在on后加the吗?为什么? Are you allowed to go out on school night