Question

1. I don't know how to inline skate.

2. He is good at inline skating.
3. Do you like inline skating?
4. I made him inline/in-line skate.

(Are they all grammatical? Why does it have 'inline'? What about 'in-line'? Are both expressions grammatical?)

Answer 1

They're all grammatical. A quick check of Google sites show only the one word -- "inline" used in this context.