The appropriate sign for "corner" depends what kind of
corner you are referring to. In general what you do is you use
"flat"-hands ("B"-hands) to show a corner, (as in the corner of a
room or the corner of a city block). However, if you are
talking about the corner of a picture (on the wall) you would
instead use an "L"-hand (or two index fingers) and do the sign
horizontally (up in the air).
See animation: "corner"
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