It must be easy to see which subject a pronoun talks about.
Take a deep breath through your nose and hold it.
(Is the pronoun it talking about breath or nose?)
Take a breath through your nose and hold your breath.If your students don’t do well in their exams, then they can’t be very good.
(Is the pronoun they talking about students or exams?)
Your students can’t be very good if they don’t do well in their exams.
