The teacher turned on the overhead for her class to copy the notes.
I accidentally overheard their private conversation while walking past their table at the restaurant.
I overheard a tidbit of gossip about our coworker during lunch yesterday.
No, starting a sentence with "then" does not make it a complete sentence on its own. It is typically used as a transition word indicating sequence or consequence and should be followed by an independent clause to form a complete sentence.
The hunter stalked silently through the forest, eyes trained on its prey.
She was able to achieve her goals through clever manipulation of the situation.
An antonym for overheard could be overlooked or ignored.
Overheard
I was scared when I overheard my mum and dad arguing.
I overheard a tidbit of gossip about our coworker during lunch yesterday.
The couple whispered as they did not want to be overheard by the people sitting at the next table.
It is one word.
Synonyms for the word overheard: discovered, heard, recorded
Yes I certainly can make a sentence with that word.
how can make the sentence for word mercy
Overheard.
3 syllables
I conclude that it is possible to make a sentence with the word "conclude."
Corroborative is the hardest word in the world to make a sentence for.