Many of them wanted to continue the conversation but needed to leave.

I'll probably need them to leave from the looks of this place.

"We need the money to leave the country and start new lives."

We'll need to leave pretty early in the morning- more like the middle of the night- to get there on time.

"We need to leave early enough for me to make my call from the car on the way back."

After one more, I'll then allow any who need to leave to do so.

Your degree is no longer the only thing you need to leave university with.

He needed to leave before his interest in this woman got the better of him.

"Never mind what you were going to do, we need to leave now!"

We need to leave at least one person here, to keep in contact with Earth.