be difficult to do是什么意思
be willing to do sth difficult是什么意思?
difficult to do /to be done
be+形容词(difficult) to do something造句
Drops to be very difficult是什么意思
请问有be difficult to do sth 这个词组吗?
Why do you think resolutions may be difficult to keep?
be difficult for somebody to do something怎么造句
be good to do 是什么意思
be said to do是什么意思?
be difficult (或类似于difficult的形容词)+to do中不定式为什么成分
be difficult for him to give up smoking是什么意思
find it difficult to do,