The sign for "bridge" (as in a "raised pathway") uses
the non-dominant arm to represent the driving or walking surface of
the bridge and the dominant arm to represent the underlying supports
of the bridge. The non-dominant hand is (more or less)
horizontal. The non-dominant handshape is not overly important.
I use a flat hand for my non-dominant handshape but you can use a
fist and it still means "bridge."
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