What are the pillars of fasting?
The pillars of fasting are intention and abstaining from all nullifiers of fasting from dawn to sunset.
Is it permissible for the young woman to turn the suitor down if she had no feelings for him?
Yes, it is permissible for her to do so.
What are the nullifiers of fasting?
1. Anything that enters the body cavity intentionally, even in small amounts, through an open passage such as the mouth, nose, ears, front, or back private parts.
2. Intentional vomiting.
3. Sexual intercourse.
4. Masturbation.
5. Menstruation and postnatal bleeding.
6. Insanity.
7. Apostasy.
8. Fainting if it lasts for the entire day.
Is it permissible for one to shake hands with his uncle`s daughter?
No, it isn`t because he is a non-Mahram (Marriageable) to her.