This call suffers from having two definitions that are very different,
but are compatible from the most common starting setup.
The official definition makes it a matrix ("space invader") call. Beaus
Press Left while the Belles Press Ahead and then Run/Trade/Flip Left.
The belles will often find themselves trading with another person, but,
if no one is there, they do a Phantom Run Left, or Left Loop 0.
The beau/belle identification occurs at the start of the call, based on
whatever the matrix is.
\sxvlines{b3s,b4s,g4n,g1n}
\syhlines{b2n,g4s,g3n,b3s}
before Bridge the Gap
after
\syhlines{g3s,b3n,b2s,g4n}
\syhBBBBs{b3s,b4s,.+.,.+.,g4s,g1s,.+.,.+.}
before Bridge the Gap
after
\syhlines{b2n,g4s,g3n,b3s}
\sxvCCCCsplus{.+.,.+.,.+.,.+.,b3s,g4s,b4s,g1s}
before Bridge the Gap
after
The first example above is a very common one, and is equivalent to
Tandem Twosome Fan Thru to a Wave. This has led to an alternate
usage, subject to modifiers such as Single and 3x3. Such modifiers would
normally make no sense when applied to calls that are defined as completely
general matrix calls. But they can be applied to Bridge the Gap if
Tandem Twosome Fan Thru to a Wave is taken as its definition.