改写下列句子，改写后的句子要与原句句意相同。（每空一词）
1．It seemed that he had been there．
He seemed _______ _______ _______ there．
2．The boy is so young that he can't carry the box．
The boy is _______ young _______ _______ the box．
3．I don't know which book I should choose．
I don't know which book _______ _______ ．
4．He was happy when he heard the good news．
He was happy _______ _______ the good news．
5．The boy is older so he can go to school．
The boy is old _______ _______ go to school．
Key:
1．to have been 2．too；to carry 3．to choose 4．to hear 5．enough to
