s1=c1 is a linguistic-gesture unit/chereme [in analogy with phoneme; specifically, nonvocal] representing/that is recognized meaningful conceptual subunit underlying specific gestures/gesture-phones s2 in language b1 used by b2 in order to communicate/express b3=c2 (si'o/du'u; not quote) made using body part/utensil/tool/locus c3 by motion/action/means c4
s1 (phone/speech sounds; specifically is linguistic and vocal) is a phoneme in/of segment of utterance/speech stream s2=v1 in language b1 of speaker v2=b2 in order to communicate/express b3 (si'o/du'u; not quote(?)), produced with body-parts/tools x6 at loci/in position/manner (of articulation) x7
x1 is a material conditional/'IF' statement (logical statement) saying that x2 (du'u) logically implies x3 (du'u) ("x3 is true if x2 is true; if x2, then x3; x2 being true is sufficient to guarantee the truth of x3").
x1 is a logical statement which says that x2 (du'u) being true logically implies (material implication) x3 being necessarily true, but in which the converse does not hold (it is certain that there are cases in which 'IFF' fails: x2 is not necessary for x3).
x1 is a logical statement of proposition-equivalence/is a biconditional/'IFF' statement saying that x2 (du'u) is true if and only if x3 is true ("x2 is logically equivalent to x3; x2 being true is sufficient and necessary for guaranteeing the truth of x3; x2 iff x3").