Translate the given sentences. Mind the First, the Second and the Third Conditionals.
1. The student won't pass his exams in time unless he works hard.
2. I will tell him about my problems if he appears here one of these days.
3. Mr. Smith knew the address, he would write the answer at once.
4. He would not have failed the exam if he had worked hard.
5. I will give you my text-book if you return it next week.