the antiknock is not vernal.
sent1: if something is a FISA then it is modest. sent2: the straight is a brave. sent3: if the straight is brave it is modest. sent4: the antiknock is a kind of non-vernal thing that is not ergotic if the straight is modest. sent5: that the antiknock is vernal is correct if the straight is vernal thing that is not a kind of a brave.
sent3 & sent2 -> int1: the straight is modest.; sent4 & int1 -> int2: the fact that the antiknock is both non-vernal and non-ergotic is not incorrect.; int2 -> hypothesis;
if that the lacer is a FISA hold it is modest.
sent1 -> hypothesis;
$hypothesis$ = the antiknock is not vernal. ; $context$ = sent1: if something is a FISA then it is modest. sent2: the straight is a brave. sent3: if the straight is brave it is modest. sent4: the antiknock is a kind of non-vernal thing that is not ergotic if the straight is modest. sent5: that the antiknock is vernal is correct if the straight is vernal thing that is not a kind of a brave. ; $proof$ = 
sent3 & sent2 -> int1: the straight is modest.; sent4 & int1 -> int2: the fact that the antiknock is both non-vernal and non-ergotic is not incorrect.; int2 -> hypothesis; __PROVED__