sort something out means find a solution to, put in order (e.g. There are a few problems we need to sort out)
split up (or break up) (with somebody) means separate
stand up (e.g. Alan stood up and walked out)
stick to something means continue doing something (e.g. You will lose weight if you stick to the diet.)
switch something off means stop the energy flow (e.g. The light’s too bright. Could you switch it off?)
switch something on means start the energy flow (e.g. We heard the news as soon as we switched on the car radio.)