时态怎么选1.by the middle of the 1920s the farthest corners of th

来源：学生作业帮编辑：作业帮分类：英语作业时间：2024/05/15 11:10:24

时态怎么选
1.by the middle of the 1920s the farthest corners of the earth _______ explored.
A have been B had been
为什么不是用A更好吗?还有影响.
2.after world war 2,mass immigration _____ Australia into a modern nation.
has transformen
为什么要完成时呢?一般过去时不可以吗?

1、
地球最远的角落已经在 the middle of the 1920s之前被发现了,所以只能用过去完成时
2、
World War2以后,人们是不断的向Australia移民,持续到现在,所以用现在完成时
竭诚,望采纳!

时态怎么选1.by the middle of the 1920s the farthest corners of th the four corners of the sky the middle of the the 15th day of the 8th month is the right middle of autumn the 15th day of the 8th month is the right middle of autumn英 The farthest of the world is not life or death .it's you fac in the middle of middle of.the. I's in the middle of China What’s in the middle of water? 英语翻译1 (in the middle of the 19th century ,the meaning of the by the middle/end of the month,月初怎么说呢