premise: A man wearing a blue jacket fishing in a river having a conversation with his friend with no shirt.
hypothesis: A man is having a conversation with his friend while fishing.
explanation_1: Fishing in a river is a type of fishing.
explanation_2: A man is having a conversation while fishing in both sentences.  The first is a fragment, the second is correct.
explanation_3: This man is having a conversation with his friend while he is fishing; what they are wearing is less relevant to the topic.
premise_logic: exists e1 e2 s1 x1 x2 x3 x4 x5 x6 x7 x8.(a_topic(x1) & Theme(e2,x3) & Actor(e2,x2) & v_wear(e2) & in(x3,x5) & -exists x9.(with(e1,x8) & with(x8,x9) & n_shirt(x9)) & n_friend(x8) & of(x8,x1) & n_male(x1) & Theme(e1,x7) & Actor(e1,x6) & v_have(e1) & n_conversation(x7) & (x5 = x6) & n_river(x5) & n_fishing(x3) & of(x3,x4) & n_jacket(x4) & a_blue(s1) & Theme(s1,x3) & (x1 = x2) & n_man(x1))
hypothesis_logic: exists e1 x1 x2 x3 x4.(while(e1,x4) & n_fishing(x4) & Theme(e1,x2) & Actor(e1,x1) & v_have(e1) & with(x2,x3) & n_friend(x3) & of(x3,x1) & n_male(x1) & n_conversation(x2) & n_man(x1))