If/how to prune my pear tree?

I have a pear tree in my front garden but I don't know if/how it needs pruning. Someone has mentioned spreaders?

Sorry I really don't know anything about fruit trees! 

It's about 7' tall and I believe about 4/5 years old.

I've added a pic so you can see what I'm working with. Any advice is appreciated.

Thank you.

The tree is leaning over rather, so iiwm I woud stake it well, to make sure it grows upright from now on. the stake should not touch the bark itself (you can get rubber spacers, or use tights tied into a figure 8 between the trunk and the stake itself.

Once it up straight, cut out any branches that head off in the wrong direction (crossing ones as sparkyrog suggested) to create an open framework.

You will easily be able to see fat round fruiting buds, there are plenty.

I would not cut anything else out now, but prune again about September, to reduce any branch that is too long, and to encourage new fruit buds to form

Scrape away a circle of grass around the trunk about 18ins in diameter, give the tree a decent feed (rose fertiliser, or blood fish and bone, mluch the circle with bark chips, and the tree will do you proud

Hope that helps a bit