the undercarriage is handless.
sent1: the undercarriage is not handless if the clarinetist does not grub clarinetist. sent2: the clarinetist grubs clarinetist and does flurry. sent3: that the undercarriage is not unpropitious is correct. sent4: if the clarinetist does grub clarinetist then the mustang grubs pier.
sent2 -> int1: that the clarinetist does grub clarinetist is not wrong.; sent4 & int1 -> int2: the mustang does grub pier.;
the undercarriage is not handless.
$hypothesis$ = the undercarriage is handless. ; $context$ = sent1: the undercarriage is not handless if the clarinetist does not grub clarinetist. sent2: the clarinetist grubs clarinetist and does flurry. sent3: that the undercarriage is not unpropitious is correct. sent4: if the clarinetist does grub clarinetist then the mustang grubs pier. ; $proof$ = 
sent2 -> int1: that the clarinetist does grub clarinetist is not wrong.; sent4 & int1 -> int2: the mustang does grub pier.; __UNKNOWN__