题目内容：

As soon as he arrived at home ,he began to do the homework.同义句.
_____ _____ ______home,.
Upon ______ ______ ______,.
_____ _____ he arrived at home ,...

优质解答

1.Once he arrived home,...
2.Upon arriving his home,...
3.The moment...
楼上arriving不用加at...应该不对吧