Student or Learner
- Something is key to doing something.
- Something is key in doing something.
Do these mean the same thing?
Merriam-Webster's Learner's Dictionary
▪ Their votes were key in getting the bill passed.
Wikipedia:Etiquette - Wikipedia, the free encyclopedia
Treating others with respect is key to collaborating effectively in building an international online encyclopedia.
And if you want to get these people really mad () say something is 'very key.'