根据下面句意、汉语提示，在下边的横线上写出空白处所缺单词的正确形式，每空一词。
Australia is very large, but the ________(人口)is quite small．
Mr．Dong lives on the ________(第五)floor
用所给的单词的适当形式填空，使句子意思完整通顺，每条横线限填一个单词。
We hope it will be ________(sun)tomorrow, for our picnic．
Many new ________(potato)will grow from one potato planted in the ground．
I met an old friend of ________(I)in the Summer Palace last Sunday．
He did the work very ________(care)．Everybody said he had done a good job．
I couldn't understand why he was so ________(interest)in the invitation．
根据句意，用括号内所给单词的适当形式填空。
I don't like chicken ________ (sandwich)．
There were many ________ (visitor) in the zoo yesterday．
He is good at ________(skate)．