根据句意和汉语提示，写出单词的正确形式。
【小题1】 On Children’s Day, children could not hide their______________(excite).
【小题2】 He comes from the _______________(south) city of China.
【小题3】Jim is happy to live on the ____________ (twelve) floor because he enjoys the view out of the windows.
【小题4】 Mr. and Mrs. Wang will celebrate their fifteen years of ____________ (marry) this weekend．
【小题5】 The water in the river is______________(harm). You can drink it without cooking.
