occasional

"My friend told me there was something in the box, but I didn't know what it was yet. "

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

"The liftoff will occur in exactly twelve seconds."

"He intends to go to university."

"The specific of her success was her dedication to studying. "

"The sun was finally appearing from behind the clouds. "

"At this point, she seized the occasion to make her own observation."

"My sister occasionally helps me with my homework. "

"The guard blew his whistle to indicate imminent departure."

"The children's bedtime was irregularly scheduled, sometimes at 8:00 pm, sometimes at 9:00 pm. "

"I met her at a gathering of engineers and scientists."

"The teacher requires students to submit their essays by Friday. "