if Alaska had not been sold to the United States,perhaps Rus
英语翻译If there had ever been any danger that the United States
If the United States had not entered the Second World War,pr
Alaska was purchased by the United States from what country
These farmers have been to the United States .
go to United States 还是go to the United States
If the United States had built more homes for poor people in
虚拟语气,脑壳发麻if the United States had built more homes for poor
----Have you been to the romantic city,Paris?----Perhaps not
英语单选It's the first time she has been to the United States,__
It’s the first time that she has been to the United States,_
At the end of last month I had made to the United States.
He has been to many countries ,such as the United States and