Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to clean a keyboard [title] Shut down the computer and detach the keyboard connector before any cleaning procedure. [step] Do not remove or connect a keyboard while the computer is running. Doing so may damage the machine if you have a non-usb-based keyboard.

Ending1: Detaching the keyboard while the computer is running is safe when the keyboard is connected to the computer via usb. [title] For a quick cleaning, turn the keyboard upside down and use a can of compressed air to blow out any foreign matter. Ending2: This could cause a paperclip message from the owner of the computer to stick on the keyboard, triggering a crash. In the event that you have a problem with the keyboard by the end of the cleaning process, remove the keystem connector from the computer. Ending3: [title] Remove the component cover from the motherboard. [step] Remove the old component to access the new component. Ending4: Attach the other end of the wire to the original keyboard connector. Use the same type of wire that you took off the previous year's keyboard connector.

Answer format: ending1/ending2/ending3/ending4