Triangular blue and red flags flutter in the wind.
Flags on a boat blow in the wind
The blue and red flags fluttering in the wind aren't necessarily on a boat.
exists s1 s2 s3 x1 x2 x3.(n_wind(x3) & a_topic(x1) & in(x1,x3) & n_flutter(x1) & of(x1,x2) & n_flag(x2) & a_red(s3) & Theme(s3,x1) & a_blue(s2) & Theme(s2,x1) & a_triangular(s1) & Theme(s1,x1))
exists x1 x2 x3 x4.(n_wind(x4) & a_topic(x1) & on(x1,x2) & in(x2,x4) & n_blow(x2) & of(x2,x3) & n_boat(x3) & n_flag(x1))