when

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

"In her English class, Maria learned that a participle, like "running" in "running shoes," can act as an adjective. "

"Let me introduce you to my friends."

"Consider that we’ve had three major events and the year has hardly begun."

"My sister is very helpful, especially when it comes to organizing things. "

""Because of unforeseen circumstances, the school trip was cancelled." "

"The circumstance of the heavy rain delayed the school bus. "

"Sire, do I have your permission to execute this traitor?"

"His impatience was evident as he waited for the bus, tapping his foot nervously. "

"The main ingredient in Grandma's famous chocolate chip cookies is butter. "

"The interrogative "who" is often used in classroom discussions to encourage student participation. "

"Words cannot express the love I feel for him."