根据下列句意,用括号内所给英语单词的适当形式填空
It's difficult for the kid _____(carry)the heavy box.

If you have any _____(difficulty),call me at once.
Now there is less _____(live)space for each family than before.
One _____(five)of the water is from the river
60 percent of the students in our class ______(be) interested in the movie.