His jaw [mouth] went slack.
彼の口がぽかんと開いた
His mind was on other things.
彼は他のことを考えていた
His mood mirrored the gloomy weather.
彼の気分は憂うつな天候を反映していた
His name alone made the enemy shudder.
彼の名前を聞いただけで敵は震え上がった
His nose was stuffed up.
彼は鼻が詰まっていた
His red eyes betrayed (the fact) that he had not slept.
赤い目をしていたので彼が眠っていないことがわかった
His right arm had gone to sleep below the tourniquet.
彼の右腕は止血帯から下の感覚を失っていた
His second book was a notch better than his first.
彼の２回目に書いた本は最初のものより一段とよいできだった
His shirt was spotted with blood (stains).
彼のシャツには点々と血（のしみ）がついていた
His silence gave rise to an absurd rumor.
彼が沈黙していたのであらぬうわさを生んだ
