어 넘어가다

be taken in; sun goes down

An "-아/어" form plus 넘어가다 "go over, cross". Two set phrases account for most of these lines. 속아 넘어가다 is being completely taken in by a lie — will Mum fall for it this time, Iran was fully taken in, they'd have fallen for it. 해 넘어가다 is the sun going down over the horizon. The bare repeated 넘어가 넘어가 is a shout to move on past something, which is the same verb doing its everyday job.