dà gài
他嘴上不说，心里却捉摸了个大概。
Tā zuǐ shàng bù shuō, xīn lǐ què zhuōmo le gè dàgài.
He didn't say it out loud, but he had a general idea in his mind.
他把情况做了个大概的分析
Tā bǎ qíngkuàng zuò le gè dàgài de fēnxī
He made a rough analysis of the situation
这件事我记不太清，只有个大概的印象。
Zhè jiàn shì wǒ jì bù tài qīng, zhǐ yǒu gè dàgài de yìnxiàng.
I don't remember this matter very clearly, I only have a rough impression