imminent是adj.表示是即将发生的,这是一个对将来的时间虚拟.
这里的条件从句是"When for the first time the United States imported more oil than it exported",主句是" Americans should have realized……" 而对将来时间的虚拟主句谓语用should+动词原形/did/were to do.
imminent是adj.表示是即将发生的,这是一个对将来的时间虚拟.
这里的条件从句是"When for the first time the United States imported more oil than it exported",主句是" Americans should have realized……" 而对将来时间的虚拟主句谓语用should+动词原形/did/were to do.