bǐrú qǐngzuò hěn zìrán máfan nǐ zuò jiù qíguài dàn máfan nǐ bāng wǒ kàn yíxià hěn zìrán

比如“请坐”很自然，“麻烦你坐”就奇怪；但“麻烦你帮我看一下”很自然。

For example, saying 'please sit down' is very natural, while 'could you sit' sounds strange; but 'could you please take a look for me' is very natural.