be difficult to do sth是什么意思

be
difficult
to
do
sth
做某事是困难的
例句:
1.
He
has
to
do
difficult
surgery
with
his
special
skills
that
he
studied
at
the
university.
他在他从事研究的大学里用他特殊的天赋作了很艰难的手术。