题干
On his _________ from Australia we gave him a welcome party.
A：came back
B：return
C：return back
D：went back
答案(点此获取答案解析）
B
On his _________ from Australia we gave him a welcome party.
A：came back
B：return
C：return back
D：went back
中，角
、
、
成等差，边
、
、
成等比，则