Student or Learner
1. I can swimming
2. I am able to swimming
Which one is better? which one is most usually be used?
Neither. I can swim. I am able to swim.
I use "I can" more often than "I am able to."
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.