tā / suī / rán / nián / jì / bù / xiǎo / yán / tán / jǔ / zhǐ / què / xiǎn / de / hěn / yòu / chǐ

他虽然年纪不小，言谈举止却显得很幼齿。

Although he is not young, the way he talks and behaves seems quite naive.