根据句意,用所给单词的适当形式填空。
How happy we were to see the safe ____________ (arrive) of all the Chinese fishermen!
The ____________ (two) Summer Youth Olympic Games will be held in Nanjing in August,2014.
Compared with the young,People in the old days were living more ____________ (comfortable)
The ____________ (strict) his teacher is with him, the more progress he will make.
Children under 12 can’t be left at home by ___________ (them) in some states of America.