MOTOBIKE- QUICK ANSWER?

i am 17 and have passed my CBT and have a provisional , i ride a gilera 125cc, i legally have to show L plates? And i cant legally carry pillions, i know this, i am simply curios. but if i take my l plates off, how will the police know if i have the correct licence or not, is there anyway i can carry a pillion with the current license i am on (unofficially)