concurrent

Compared meaning: happening at the same time (adjective).

比较义项：同时发生的（形容词）。

• simultaneous

  Emphasizes that two or more events happen at exactly the same instant; typically used for brief, single events (announcements, explosions, flashes) rather than ongoing states.

  强调两个或多个事件恰好发生在同一瞬间；通常用于短暂的单一事件（如宣布、爆炸、闪光），而不是持续的状态。

  The fireworks were simultaneous, bursting across the sky at the exact same instant.

  烟花是同时的，在同一瞬间划破夜空绽放。

• concurrent 本词

  Describes states, processes, or periods that overlap or run in parallel over a stretch of time, not necessarily starting or ending together; common in formal, legal, or technical contexts.

  描述在一段时间内并行进行或重叠的状态、过程，不要求同时开始或结束；常见于正式、法律或技术语境。

  He is serving two concurrent sentences for the related crimes.

  他因相关罪行同时服两项刑期。

Both mean happening at the same time, with different focus. Simultaneous stresses events at exactly the same instant, usually brief, like announcements or flashes. Concurrent stresses states or processes overlapping over time, without needing the same start or end; common in legal or technical contexts.

两个词都表示“同时”，但 simultaneous 强调两个或多个事件精确地发生在同一时刻，常用于单一、短暂的事件；concurrent 强调两个状态、过程或时间段在同一时期内并行存在或重叠，不要求同一时刻开始或结束，常见于正式、技术或法律语境（如刑期、进程）。