晶体模型:分别翻译:once a month.和twice a month .和three time a month.

分别翻译:once a month.和twice a month .和three time a month. 翻译:Twice a month 一月一次是once a month ,两次是 twice a month，是不是三次后都是序数词？ after a month 和in a month 有什么区别? a month or two's absence应怎么翻译 a two-month 翻译Once you make a promise , you should keep it month请翻译 once upon a time Once upon a century