sometime

"The unstated rule in our house is that you do your dishes after every meal. "

"My grandmother taught me how to bake cookies when I was a child. "

"My erstwhile boss now works for a competitor. "

""In the sentence 'Someone left a note,' the word 'someone' is an indefinite, because we don't know who left the note." "

"It turned out the shoplifter had a lot of previous."

"My formerly quiet neighborhood is now very busy with new construction. "

"My sometimes neighbor, a retired teacher, still visits the school occasionally. "

"I stopped at the traffic lights."

"My brother and I both attend the same high school. "

"My occasional helper at the bakery is a retired teacher. "

"A former president;  the former East Germany"

"The university hired a new lecturer to teach history. "