Open the brackets. Use third or mixed condition.
1. I would have given Susan her books if! (meet) her.
2. If she (not take) sleeping pills last night, she wouldn't be sleepy today.
3. If you had invited him, he (be) here now.
4. You (understand) the plot of the film if you had read the book.
5. Florence would be a famous actress if she (not enter) the musical college.