One of my favorite tags in Italian is “dai” which the blog Dolce Vita explains in the following excerpt,
“Dai” said with an irritated tone can mean “enough” or “stop it”. It can also mean “come on” in all its many forms – impatience, encouragement and the gritted teeth of effort or tension if you’re following you favourite football team in that moment and it’s about time they scored a goal.
“Ma dai” can indicate mild suprise, incredulity or even suspicion that your interlocutor is pulling your leg. It can be a kind of “as if” or “stop having me on”. “Dai” said with a lowered tone and widened eyes will often be found in gossip and can mean “tell me more”!
In Portuguese, ‘vai’ can be used as an informal tag on the end of a statement such as when someone says “me leva, vai!” (c’mon, take me!). Just a hypothesis based on the huge influx of Italians to Brazil during the time prior to and just after the turn of the last century.