How to do a backbend against a wall<br>Find a good, clear spot. Find a wall space that is clear of any obstructions such as furniture, plants or sharp objects. It should have nothing that could injure you near it.
You must always do backbends indoors
The context doesn't state that you need to be indoors you just need a clear wall which you can find outside. The system doesn't understand that
( z1 obligate :ARG2 ( z2 bend :ARG0 ( z3 you ) :direction ( z4 back ) :time ( z5 always ) :location ( z6 indoors ) ) )