This is the 9533rd most frequent Portuguese word.
conheçam
"Conheçam" means "that they know" or "that they meet," used as a third-person plural present subjunctive form of the verb "conhecer."
The word 'conheçam' here is used in the present subjunctive to express a wish about the future.
Espero que vocês conheçam o novo colega de trabalho.
I hope you meet the new colleague at work.
In this sentence, 'conheçam' is in the subjunctive mood to express a blessing or hope.
Que vocês conheçam sempre novas oportunidades na vida.
May you always discover new opportunities in life.
The word 'conheçam' is used in the present subjunctive to indicate necessity in regard to the students knowing historical facts.