歌手上台的时候，观众都站起来了。

Gēshǒu shàngtái de shíhòu, guānzhòng dōu zhàn qǐlái le.

When the singer went on stage, the audience all stood up.

新总统上台后推出了一系列改革措施。

Xīn zǒngtǒng shàngtái hòu tuīchū le yì xìliè gǎigé cuòshī.

After the new president took office, he launched a series of reform measures.

轮到她上台演讲了，她有点紧张。

Lún dào tā shàngtái yǎnjiǎng le, tā yǒudiǎn jǐnzhāng.

It was her turn to go on stage to give a speech, and she was a little nervous.