关于periods of 和 a period of的英语问题

A period of five miss a period of there were long periods when we had no news of him.period不可数 long periods of over a period of time over a period of five the final part of a period of 金融英语的一句话.the income statement covers a specific period of ti it's + a period of time + before/since 的区别? 关于英语of的问题of的用法,最主要的问题是例如,flower of picture和picture of flower 英语翻译 over a period of time A period of time 用于什么时态