Drag the correct words to fix this journal entry. One sentence has a mistake!

Context: Tom is writing about his progress with a new fitness routine.

"Week 1: It's hard to exercise every day. ❌ Week 4: I'm finally good at to run long distances! Wait… that doesn't look right."

Help Tom correct his mistake:

"I'm finally good at running long distances!"

The correct answer is running.

After the preposition at (in "good at"), use a gerund (-ing form), not a to-infinitive. "Good at to run" is incorrect!