Look at the sign _______! We shouldn't park our car here.
No one knows ____ .
---I seem to be lost. Could you tell me _____?---Sure. You can take the No.3 bus to get there.
----Please tell me ___________________an hour ago.---He rode his bike.
Do you know__________? –He came here by train.
—The light in his room is still on.Do you know________?—In order to prepare for the coming exam.