Tā de bǎngzi hěn cūzhuàng, yí kàn jiùshì jīngcháng duànliàn de rén.
His arms are very muscular - clearly someone who exercises regularly.
Tips
usage
膀子 specifically refers to the upper arm. It is more colloquial than 手臂 (arm in general) or 上臂 (upper arm in medical contexts). Also used for a bird's wing.
