单项选择题
Electricity （） by the Greeks a good many years ago.
A.was first found
B.was first discovered
C.has first been discovered
D.was seen first
点击查看答案&解析
相关考题
-
单项选择题
Before she left on the trip, she（） hard.
A.trained
B.has trained
C.would trained
D.had trained -
单项选择题
You（）to lock the door at night.
A.should
B.ought
C.must
D.shall -
单项选择题
-- Hello, could I speak to Don please? --（）
A.Who are you
B.What’s the problem
C.Are you Jane
D.Who’s speaking?
