V. Complete the sentences with the given words in their proper forms（用括号中所给单词的适当形式完成下列句子）
【小题1】My grandparents live on the ___________ (five) floor.
【小题2】Can the boys keep ___________ (them) promises?
【小题3】Don't leave the batteries here. They may ___________ (pollution) the land.
【小题4】What do you ____________ (usual) do on Sundays?
【小题5】Kitty would like to go ____________ (swim) with her parents.