During his sentence, he participated in a work-release program, working outside during the day and returning to prison at night.

work-release 是由 work（工作）和 release（释放）组成的复合名词。work 指"工作"，release 指"释放、解除"。 work-release program 指一种允许囚犯白天外出工作、晚上返回监狱服刑的"工作释放计划"，旨在帮助囚犯逐步回归社会。