1 sentence

1. 他为了完成实验，整整三天不知疲倦地工作。

   tā wèi​le wán​chéng shí​yàn, zhěng​zhěng sān tiān bù​zhī pí​juàn de gōng​zuò.

   He worked tirelessly for three whole days to complete the experiment.

   Source: Dong Chinese Dictionary