他一直保持沉默。

Tā yìzhí bǎochí chénmò.

He kept silent the whole time.

为什么每次我问你这个问题，你就会选择沉默？

Wèishénme měi cì wǒ wèn nǐ zhège wèntí, nǐ jiù huì xuǎnzé chénmò?

Why do you choose to stay silent every time I ask you this question?

她一直保持沉默。

Tā yīzhí bǎochí chénmò.

She has remained silent.