sentence 1: How do I know if I'm good?
 sentence 2: How do I know what I'm good at? sentence 1: Why is sex important in a good relationship?
 sentence 2: Is sex is required in relationship? sentence 1: How and when can I fill the form of Improvement exam of class 12 in 2017?
 sentence 2: Is class 12 improvement exam forms are out for 2017?
not same meaning
same meaning
same meaning