题目内容
(请给出正确答案)
[主观题]
If oil______on the frozen north coast in the 1960s, an 800-mile pipeline would not have be
en constructed to bring it to the south coast.
A.was not discovered
B.was discovered
C.had not been discovered
D.had been discovered
提问人:网友ytsky2008
发布时间:2022-01-06