下列句子中划线词语使用不正确的是[ ]
A．这件事发生在很久很久以前。
B．电子计算机发展很迅猛。
C．电话是19世纪贝尔发现的。
答案：C
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.
比位能是指（）流体的位势能。
A.单位质量
B.单位重力
C.单位体积
D.单位摩尔
