企源知识库

It was not until the 1860s_________Abraham Lincoln declared the last Thursday of November to be a national holiday.
A、 whenever
B、 that
C、 when
D、 as
【正确答案】：B
【题目解析】：此题考察的是强调句。It is/was …that是强调句型，如果be动词后面接的是人则可以用who连接后面的分句，其他强调内容都只能用that。