on a year ago 还是in a year agoon the other day 还是 the other day不用介词.这有没有规律可循

on a year ago 还是in a year agoon the other day 还是 the other day不用介词.这有没有规律可循 He take party in the tennis club a year ago还是He join the tennis club a year ago half a year ago. The johns stayed in HeFei （ ）.A.for half a year B.half a year ago A Year Ago Today 歌词 A Year Ago Today 歌词 “一年前”翻译成英语应该是a yearr ago 还是one year ago?一月前呢 The King lived in London a year ago .对in London进行提问 英语被动句6、He made me do that for him .I 空 空 空 空 that for hin.7 Did they build a bridge here a year ago?空 a bridge 空 here by them a year ago?8 we'll put on an English play in our school.An English play 空 空 空 on in our school We were listed on the Shanghai Stock Exchange a year ago. l came to study in the United States a year ago will you be free________next year?A in B / C on Our foreign teacher has travelled to five cities in China------ .A last year B a year ago C nest yer D this year 一句话,我钻牛角尖了,朋友们指点一下一年之前,一年之后a year ago,a year later,还是 one year ago, one year later若是都可以的话,在语法上,或者习惯上有什么不同呢谢谢哈~~~ 关于介词的使用There are four seasons （ ）a year括号里用 on 还是用 in on a visit还是in a visit ? on a trip还是IN A TRIP in a cloth还是on a cloth