there are lots of escapes from the mount position. i suggest going to a jiu jitsu gym and learn some basics.

BITE THEM

If someone's on top of you, secure one of their arms and bridge and roll to the side so that you end up inside their guard position.

If someone's carrying you, knee to the groin, elbow to the face, bite, eye gouge.

Grab his ears, pull his head towards you…..And bite his nose of

you planning to be picked up by a tribesman?

if somebody is carrying you you can take it that they have left some form of weapon on your body open
be it your head arm or leg.

as for when they are on top of you pinning you down im no BJJ expert but i'm guessing small joint manipulation would come in.
or maybe some form of bite etc

when someone is on top of you and holding your arms down, bridge out.bridging is where you get your legs up,bending at the knees with your feet planted firmly on the ground a few inches from your butt and spread shoulder width for stability.then thrust your pelvis forward one one side only, using the leg on the same side of the hip you are pushing with.the goal is to roll over so that you are on top of them, putting you in a more advantageous position.look it up it is a very basic and useful technique used in grappling and mma.and if someone is carrying you just try to roll out of it or make take an elbow to the top of their spine or if they are carring you facing forward, give them a powerful elbow to the solar plexus, the small gap about an inch below their sternum.make that move when they exhale and they are almost garunteed to throw up or pass out, or at the very least get winded seriously.someone also mentioned throwing them up and rolling over so you are laying belly down.never do that.ever.that leaves your back open and actually leaves you MORE vulnerable.

If their hands are on the ground holding your hands – you are OK. They need their hands to attack, so just be patient and wait for them to let go. When they let go you have options – striking, sweeps, reversals, armlocks, headbutt, etc. I'm going to guess that you don't understand what some of that is, which indicates that you need training to defend yourself.

You won't learn self defense from the internet. You CAN learn self defense from an instructor.

If someone's carrying you, tell them where you want to go, and tip them when they drop you off at your destination. If possible, get a receipt since it may be tax deductible.