有情态动词时主动语态怎样变为被动语态，例句

Question

如题所述

Answer 1

含有情态动词的主动句变成被动句时，由“情态动词＋be＋过去分词”构成，原来带to的情态动词变成被动语态后，to
仍要保留。例如：
We
can
repair
this
watch
in
two
days.
→This
watch
can
be
repaired
in
two
days.
They
should
do
it
at
once.
→It
should
be
done
at
once.