Tā néngyán-shànbiàn, jǐ jù huà jiù bǎ duìfāng shuō de yǎkǒu-wúyán.
He's so persuasive that a few sentences left the other side speechless.
Tips
usage
Mostly praise: articulate and persuasive, the opposite of 不善言辞 "not good with words". Compare 花言巧语, sweet talk meant to deceive, which is always negative.