Can input pin floating (openning)?Can output floating? why?

在设计中，单元的输入端可以悬空吗？输出端哪？

Gao Hua, the cultural counsellor in Chinese Embassy in Burma made an openning speech.

中国驻缅甸大使馆文化参赞高华阁下为大家做了亲切的讲话并宣布比赛正式开始。

For openning up the international market, we established the International Trade Department.

我公司为开拓国际市场，设立了专门的国际市场部。