Ruby: test returns ArgumentError

Greeting Stackoverflow fellow people! I'm learning Ruby and as one of the intro exercises I'm meant to type "test" and receive "nil"

However I receive this instead:

ArgumentError: wrong number of arguments (0 for 2..3)
    from (irb):15:in `test'
    from (irb):15
    from /usr/bin/irb:12:in `<main>'

Does anyone know if I need to fix something, because I can't seem to find anything on this anywhere I've looked so far.

Thanks in advance!