Source<br>Ray grabbed a pair of pants to wear for the day. He noticed there was a big red stain on them. Upon further investigation, he saw more of his clothes were stained. Ray went to his dryer for more answers. Inside was two broken red pens.
Ray noticed 2 big stains on his pair of pants
It says Ray found a big red stain on his pair of pants.  A implies 1 not more than one.  Not sure why the system got it wrong.
( z1 notice :ARG0 ( z2 person :name ( z3 name :op "Ray" ) ) :ARG1 ( z4 stain :quant 2 :mod ( z5 big ) :location ( z6 pair :quant 1 :quant-of ( z7 pants :poss z2 ) ) ) )