'The popcorn comes at a price', 'The popcorn is not free', 'The popcorn Price tag $10', 'You should purchase the popcorn' or, merely, 'The popcorn just isn't free'. The statement, 'You will take your baby on the flight free of cost' could be in opposition to 'You must spend to choose your child with a plane' or 'It isn't really free', or informally