and down the left side are terms "is" -- "did" -- "can"
what you then do is "cross multiply" a top term with a side term to get different ways of asking questions:
what is
when is
where is
WHAT WHEN WHERE WHICH WHO WHY HOW
IS what
is when
is where
is which
is who
is why
is how
is
DID what
did when
did where
did which
did who
did why
did how
did
CAN what
can when
can where
can which
can who
can why
can how
can
WOULD what
would when
would where
would which
would who
would why
would how
would
WILL what
will when
will where
will which
will who
will why
will how
will
MIGHT what
might when
might where
might which
might who
might why
might how
might
12/3f/93