ATTEMPTING TO ENTER AN EXPRESSWAY ENTRANCE RAMP, I ACCELERATED THE VEHICLE TO AVOID A CAR CLOSING RAPIDLY FROM BEHIND. THE CAR WAS HEADING STRAIGHT AND I MADE NO STEERING INPUT TO THE THE REAR END ABRUPTLY MOVED TO THE RIGHT AND I WAS UNABLE TO COUNTERSTEER SUFFICIENTLY TO AVOID HITTING A VEHICLE IN THE LANE TO MY RIGHT. THIS INITIAL COLLISION CAUSED FURTHER LOSS OF CONTROL WITHIN MY VEHICLE AND THE OTHER VEHICLE, AND WE COLLIDED A SECOND TIME.