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

——Where is Mary?

——She is busy _________ for the exams(考试).