Question

How to determine that word is a 'root' word? Such as speaking, the root word is speak.

Answer 1

just remember the verb or the action word.

• Speaking - speak
• Talking - talk
• Walking - walk
• walked - walk
• talks - talk

or try removing "ing" "ed" "es/s"

just remember that there are words that really ends with the above suffices.

I hope that helps.