问题详情:
Not until the early years of the 19th century______ what heat is.
A. did man know B. man had known C. man knew D. had man known
【回答】
A
知识点:倒装与省略
题型:选择题
问题详情:
Not until the early years of the 19th century______ what heat is.
A. did man know B. man had known C. man knew D. had man known
【回答】
A
知识点:倒装与省略
题型:选择题