premise: A man with a gray shirt is rehearsing in front of a empty drum set.
hypothesis: The band's singer rehearses.
explanation_1: A singer is not necessarily a man.
explanation_2: First sentence does not imply he is a singer, but could just play an instrument.
explanation_3: Being a man does not mean that he is a singer.
premise_logic: exists e1 e2 s1 s2 x1 x2 x3 x4 x5.(in(e1,x3) & of(x3,x4) & Theme(e2,x5) & v_set(e2) & (x4 = x5) & n_drum(x4) & a_empty(s2) & Theme(s2,x4) & n_front(x3) & Actor(e1,x1) & v_rehearse(e1) & with(x1,x2) & n_shirt(x2) & a_gray(s1) & Theme(s1,x2) & n_man(x1))
hypothesis_logic: exists x1 x2 x3.(n_rehearse(x2) & of(x2,x3) & n_singer(x3) & of(x2,x1) & n_band(x1) & a_topic(x2))