Start of a riddle

• "___ the Frequency, Kenneth?"
• "___ My Line"
• Asking how to create starter in a stew, tell me the plan!
• "__ new with you?"
• "___ the big idea?"
• 4 Non Blondes "Scream from the top of my lungs, ___ going on?"
• "__ the matter?"
• "____ Happening!!"

Wiktionary Word definitions in Wiktionary
n. (plural of what English) Used as a stand-in to collectively pluralize arbitrary instances of things. Often used along with whys, hows, etc.