the apple is difficult to reach.------is------to reach the apple.

问题描述:

the apple is difficult to reach.------is------to reach the apple.
the apple is difficult to reach.
------is------to reach the apple.
he is too young to go to school now.
he is-----old------to go to school now.

---It---is--difficult----to reach the apple.

he is---not--old--enough----to go to school now