premise: A male and a female with a black hat, and sunglasses stop and talk.
hypothesis: Similarly dressed couple stops to discuss plans.
explanation_1: You can not infer it's a couple.
explanation_2: Not all male and females are couples.  Stopping to talk does not mean they are going to discuss plans.
explanation_3: Even though the man and the woman are dressed similarly, they do not have to be a couple.
premise_logic: exists e1 s1 s2 x1 x2 x3 x4 x5 x6 x7 x8.(a_topic(s1) & subset_of(x4,s1) & Theme(e1,x6) & Actor(e1,x5) & v_sunglass(e1) & n_talk(x8) & n_stop(x7) & subset_of(x8,x6) & subset_of(x7,x6) & (x4 = x5) & n_female(x4) & subset_of(x2,s1) & with(x2,x3) & n_hat(x3) & a_black(s2) & Theme(s2,x3) & n_female(x2) & subset_of(x1,s1) & n_male(x1))
hypothesis_logic: exists e1 e2 p1 x1.(Topic(e2,p1) & Actor(e2,x1) & v_stop(e2) & exists e3 x2.(Theme(e3,x2) & Actor(e3,x1) & v_discuss(e3) & n_plan(x2)) & n_couple(x1) & Theme(e1,x1) & v_dress(e1) & r_similarly(x1))