what should you do when you your ---- your experiment?
问题描述:
what should you do when you your ---- your experiment?
have finished
答
what should you do when you __have finished___ your experiment?
译一下:当你完成了试验的时候你应该干什么?
后半句是时间状语从句,用现在完成时来表示完成这个实验的时间对我们要做what should you do这个决定的影响,所以这里用现在完成时是绝对正确的!