long time ago 前面一定要加 a 也就是一定是 a long time ago

long time ago 前面一定要加 a 也就是一定是 a long time ago a long time ago后面一定要用过去式么? A long time ago 与 Long time agoLong time ago前必须加a吗?在句子中只用long time ago,不加a,符合语法吗? Long Time Ago 歌词 A long time ago Tony worked in a lawyer's office years ago.为什么years前面不用加介词?好像It has belonged to our family for a long time. A Long Time Ago 歌词 long long time ago是病句吗 A long long time ago 歌词 a long time ago 、long long ago、once和once upon a time的区别 long long time ago 和 long long ago 有什么不同? a long time ago 的同义词 i stopped a long time ago. a long time ago 的过去时 some years ago 和long time ago一样吗如题 英语翻译是long,long time ago还是long,long time before还是long,long time later哪个? Not that long ago.请问这里的ago是什么意思?上句是：That was a long time ago. 求long time later long time ago long time befor 的翻译