もうひとりが彼の腕をつかんだ。

now; soon; shortly; before long; presently; already; yet; by now; (not) anymore; further; more; again; another; the other; interjection used to strengthen expression of an emotion (often exasperation)

one person; alone; unmarried; solitary

indicates sentence subject (occasionally object); indicates possessive (esp. in literary expressions); but; however; still; and

he; him; his; boyfriend

indicates possessive; nominalizes verbs and adjectives; substitutes for "ga" in subordinate phrases; (at sentence-end, falling tone) indicates a confident conclusion; (at sentence-end) indicates emotional emphasis; (at sentence-end, rising tone) indicates question

arm; skill; efforts; ability

indicates direct object of action; indicates subject of causative expression; indicates an area traversed; indicates time (period) over which action takes place; indicates point of departure or separation of action; indicates object of desire, like, hate, etc.

to seize; to catch; to grasp; to grip; to grab; to hold; to catch hold of; to lay one's hands on; to clutch; to understand; to grasp; to comprehend