You will understand that gravity can bend the path of light. You will understand that this bending of light depends on the mass of the source of the gravity. You will understand that objects other t...You will understand that gravity can bend the path of light. You will understand that this bending of light depends on the mass of the source of the gravity. You will understand that objects other than the Sun can act as lenses and that many instances of gravitational lensing have been seen.