Shortened form of what will and what shall(phrase)
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Use "what'll" in a sentence
"And of course ADHD Kirk attracts a loyal cadre, even after it's obvious being a cadre member has a high mortality rate; one reason the ADHD gene-set has not been eliminated is that people will follow crazy-charismatic ADHDers into the mouth of death, if only because they're curious to see what'll happen next."
"Because what'll happen, if I'm any indication, is that they might rampantly get into the franchise, devour lots of Star Trek stuff ... faster than it's being produced."
"AustHall earlier post is correct: Dick is scared of what'll come out of an investigation NOT run by the RNC."