一.
宾语从句中,主句
谓语动词如果是现在或将来时,从句可用任何所需时态。
eg.He
says
he
has
read
the
report.
二.主句是一般过去时,从句可使用过去范围的时态(
过去进行时、一般过去时、
过去完成时),除客观真理外(要用
一般现在时)
1.从句谓语用一般过去式或过去进行时
表示与主句谓语同时发生
eg.I
only
knew
he
was
studying
in
a
weatern
country,but
I
didn't
know
what
country
he
was
in.
2.从句用过去完成时,表示该动作发生在主句谓语动作之前
eg.He
told
me
that
he
had
told
Mary
about
the
meeting
already.
3.从句谓语用过去将来时,表示该动作发生在主语谓语动作之后
eg.The
reporter
asked
if
the
government
would
take
necessery
measures
to
put
down
the
to-do.