How can I fix the wire to my LED Christmas Lights?

How can I fix the wire to my LED Christmas Lights?

The christmas lights at my house stay up all year round but are left unplugged, they work fine each year but my rabbit decided he wanted to chew through them. There are two sets of lights and both have 4 wires wrapped around each other which connect to a plug... is there any way of fixing them, as i dont know which of the 4 wires go the the other 4 where they were chewed???