He kept a straight face the whole time and didn't cry.
Tips
usage
běng is the reading for holding a tense, expressionless face: 绷着脸 (to keep a stern face). Pulling a rope tight or a bandage is the separate bēng reading.
Left silk radical, the side form of 糸, twisted strands of silk. 绷 originally meant to bind something tightly with silk cord, hence to stretch taut. Same family: 绑, 绳, 紧, every cord-and-binding verb.
Right 朋 supplies the sound, péng drifting to bēng through a p and b alternation, and the related 蹦 (to bounce) shares the same phonetic. 朋 itself pictures two strings of cowries hung side by side, hence pair and friend. Pure phonetic here; the meaning doesn't carry over.
