Question

归纳祈使句的句型结构,区别have to与must的用法？

Answer 1

have
to
是客观的情况，不以人的意愿为前提，人是无法改变这个状态的。如my
mother
was
ill
yesterday,
i
have
to
take
care
of
her.
or
,it
is
raining
heavily,we
have
to
stay
in
the
classroom.
而
must
则是主观情况,可做可不做的，没有义务一定要做。如my
room
is
dirty,
my
mother
says
that
i
must
clean
my
room.如果我不嫌弃
，我也可以不用打扫，含有主观意志。

Answer 2

我个人总结的与一些教材上不同，
L型：Let
sb
do
sth
Let's
go
home.
V型：look
at
the
picture.
B型：be
careful.
N型：No
photos.
祈使句表达请求命令和建议,主语是you常省去,否定前面加动态Don't...
have
to
后面加动词原形，must后面也加动词原形.害我的词义是必须不得不,表示客观,外在环境影响的,must
表示主观意愿,意思是必须.