If a movement is convulsive, it is sudden, strong, and the person cannot stop it. The body jerks or shakes hard, the way it does in a fit. Doctors use the word for that kind of shaking.

If a movement is convulsive如果一個動作是convulsive，it is sudden, strong它就是突然、劇烈的，and the person cannot stop it而且當事人沒辦法停下來。The body jerks or shakes hard身體會猛然抽動或劇烈顫抖，the way it does in a fit就像癲癇發作時那樣。Doctors use the word for that kind of shaking醫生會用這個字來形容那種顫抖。

Writers also use it for other bursts you cannot hold back: convulsive laughter, convulsive sobbing — the laugh or the cry takes over. It sounds a little like a doctor-word, and a little formal. In easy talk, people more often say a sudden jerk, or she could not stop shaking.

Writers also use it for other bursts you cannot hold back作家也會用它來形容其他你忍不住的爆發：convulsive laughter, convulsive sobbing像convulsive laughter（狂笑）、convulsive sobbing（嚎啕大哭）——the laugh or the cry takes over笑或哭整個接管了你。It sounds a little like a doctor-word它聽起來有點像醫學用語，and a little formal也有點正式。In easy talk在輕鬆的對話裡，people more often say a sudden jerk人們比較常說a sudden jerk，or she could not stop shaking或說she could not stop shaking。

Though actually, it is not only for a medical fit: a convulsive gulp, a convulsive shake of the shoulders — any movement that hits hard and will not be controlled.

Though actually不過其實，it is not only for a medical fit它不只用在醫學上的癲癇發作：a convulsive gulp像a convulsive gulp（猛然一口吞下）、a convulsive shake of the shoulders或a convulsive shake of the shoulders（肩膀猛然一抖）——any movement that hits hard and will not be controlled任何來得又猛又控制不住的動作都可以用。