Is it legal to print slogans at will?

1) Police warning: Only in case of emergency, the fault will be prosecuted.

2) Lift the cover, remove the seal and press the button in case of emergency.

Don't talk to the driver.

4) Do not carry, pull down the carrier-open the door.

5) For your own safety, please hold the handrail.

6) danger! !

7) Location of fire extinguisher: under the seat.

8) No handling, no inclination

9) Please give your seat to someone who really needs it.