Fire burns. What kind of verb burn is-

Burn is an intransitive verb.
- An intransitive verb is the opposite of a transitive verb: it does not require an object to act upon.
- সুতরাং burns একটি intransitive verb .
- A transitive verb is a verb that requires an object to receive the action.
- Ex:The kids like pickles.
যে verb অন্য কোন verb এর সাহায্য ছাড়া স্বাধীনভাবে বাক্যের অর্থ প্রকাশ করতে পারে না তাকে auxiliary verb বলে।

Source:Advanced Learner's Grammar and Composition by Chowdhury and Hossain