Reading between the lines is also known as inferring. It is when the information isn't explicit but you have to do some digging for it and it is not out of reach, therefore a reading between the lines question is a question where it doesn't give you all of the info, but you have to work out some of it for yourself.
I always wanted to lose weight and following people who motivate you and help you through the stuff helps and I always tried to keep a positive mind to stay focused on what I wanted.