1樓：前鴻暉
先要看這個句子是描述過去發生的事情或是發生在未來, 理論上不可能是現在式除非表達 “經常” 的做法
英文的句型前後文與中文不同, 要說成 “他們休息了一會兒,當他們感到累的時候”
1.發生在過去
they took a rest (或 had a rest) while feeling tired
2.指 “他們一般經常的做法”
they usually take a rest while feeling tired.
3.未來會發生的事情
they will take a reset while feeling tired
2樓：諸鈺
whenever they feel tired ，they take a (short) break。
3樓：
when they feel tired, they rest for a while.
4樓：顏燕婷
they had a rest when they felt tired.