They learned from the textbook that New York the largest city in the world

问题描述:

They learned from the textbook that New York the largest city in the world
A was
B were
C is
D being

C.
在这个句子里“纽约是世上最大城市”是事实.事实就因该用现在实,除非在句子的时间这事实已经不是事实了.