This is the 2740th most frequent Catalan word.
avisen
"Avisen" means "they notify" or "they warn" in English.
In this sentence, 'avisen' is used as an imperative verb form addressed to 'you' to command the action of notifying.
Si escoltes un soroll, avisen als veïns de seguida.
If you hear a noise, notify the neighbors immediately.
Here, 'avisen' is used to describe a habitual or current action where the authorities warn of something.
Les autoritats avisen de possibles tempestes durant el cap de setmana.
The authorities warn about possible storms during the weekend.
In this example, 'avisen' refers to a recurring action in the present tense, showing what 'they' regularly do.