If the old man had been more careful, he might have not slipped over the icy road.（)
查看答案
I finished my homework until ten last night.（)
He will not go to bed until his mother comes back.（)
If cars are replaced by private planes, there would be severe traffic jams in the sky.（)
The reason why he was absent is because he was ill.（)
微信支付 
支付宝支付