a stupid person: often used to describe yourself when you have done something silly or when you feel you are being treated unfairly傻瓜,易受骗者(常指自己)
I suppose muggins here will have to take care of the cat when they go on holiday (= I will have to do it but I don't want to).我想只有像我这样的傻瓜才会在他们去度假时替他们照看猫。