How does it work?
Sandwich courses normally last for four years at degree level, with work experience or foreign studies normally taking place in your third year. Where you go and what you will do depends on the subject; modern languages students might study at a foreign university, business students might work with companies either in Britain or abroad, while science students might work in a laboratory.
Some universities arrange placements for you, but others expect you to find one yourself. You might do this by writing to employers directly, or by applying to a scheme like Erasmus if you’re looking to go abroad.