Boyle's law relates pressure and volume. It states that pressure and volume are inversely proportional, or in other words, as one increases, the other decreases.
Gay-Lussac's law states that temperature and pressure are directly proportional, or in other words, if one increases, so does the other, and if one decreases, so does the other.
Charles's law states temperature and volume are directly proportional.
Avogadro's law relates number of moles and gas and the volume.