单项选择题
A．keep after a flying target B．hit a flying saucer C．fire straight at a missle D．keep chasing the enemy’s tanks
A．a computer game B．an underwater game C．how to use modem weapons on your enemies D．an army training exercise
A．gain the skills of using your guns B．wipe out a score tanks C．hunt a number of enemy's saucers D．kill some supertanks or missiles