Fill in the blanks by using passive voice1
As we all know, both the Summer and Winter Olympic Games (held )every four year
The first Olympic Games (held)in Greece in 1896
Mordern cell phones are more than just phones---they (use) as cameras and radios
After years of hard work, parts of states (put) back together and missing pieces (replace)
In order to protect the environment ,the number of visitors (should limit)
are heldwas heldare being usedhave been puthave been replacedshould be limited语态 (voice) 是个语法范畴,它是一种动词形式,表示动词的主语与该动词所表示的动作之间的主动和被动关系
动词的被动语态由“助动词 be+ 及物动词的过去分词”构成
当主动句变为被动句时,原来的宾语变成了主语,原来的主语变成了介词 by 的宾语
We cleaned the classroom yesterday
昨天我们打扫了教室
The classroom was cleaned by us yesterday
昨天教室被我们打扫了
一般现在时: am / is / are done一般过去时: was / were done一般将来时: shall / will be