Four elderly people sitting under a white tent playing musical instruments.
Four old people are sitting under the tent playing music.
Old is a synonym of elderly.  Playing music is done with musical instruments.
exists e1 e2 s1 s2 s3 x1 x2 x3 x4 x5.(a_topic(x1) & under(e1,x3) & Theme(e2,x5) & Actor(e2,x4) & v_play(e2) & n_instrument(x5) & a_musical(s3) & Theme(s3,x5) & (x3 = x4) & n_tent(x3) & a_white(s2) & Theme(s2,x3) & Actor(e1,x2) & v_sit(e1) & (x1 = x2) & n_people(x1) & a_elderly(s1) & Theme(s1,x1) & card_eq_4(x1))
exists e1 s1 s2 x1 x2 x3.(n_music(x2) & of(x2,x3) & n_playing(x3) & a_tent(s2) & Theme(s2,x2) & under(e1,x2) & Actor(e1,x1) & v_sit(e1) & n_people(x1) & a_old(s1) & Theme(s1,x1) & card_eq_4(x1))