Related Clues:

• Punch in, as a PIN
• Sign up for a class
• Choose to compete in
• Pass through
• Take part in
• Write in
• It may start a scene
• Neighbor of a shift key
• Alternative to "return" on a keyboard
• "Door's open"
• Submit for judging
• Make a formal record of
• Drive-thru sign
• Cry from beyond a closed door
• Sign up, as for a class