江湖郎中

nà yī shēng shì yī gè jiāng hú láng zhōng

那医生是一个江湖郎中。

The doctor was a charlatan.

wèi le bì miǎn kě néng yǐn qǐ de wù jiě wǒ děi gǎn jǐn zhǐ chū tā jué bù shì yī gè guàn yú zhāo yáo zhuàng piàn de jiāng hú láng zhōng

为了避免可能引起的误解，我得赶紧指出，他决不是一个惯于招摇撞骗的江湖郎中。

I hasten to add, to anticipate possible misconception, that he was not the least of a charlatan.