我在学习中文的时候，会用中文去思考。

Wǒ zài xuéxí Zhōngwén de shíhou, huì yòng Zhōngwén qù sīkǎo.

When I study Chinese, I try to think in Chinese.

我需要安静一下，好好思考这个问题。

Wǒ xūyào ānjìng yíxià, hǎohǎo sīkǎo zhè gè wèntí.

I need some quiet so I can think carefully about this question.

他一个人在公园里散步，安静地思考明天的计划。

Tā yí gè rén zài gōngyuán lǐ sànbù, ānjìng de sīkǎo míngtiān de jìhuà.

He walked alone in the park, quietly thinking about tomorrow’s plans.