Many people run a marathon in winter.
People run a marathon no matter what the weather is.
It cannot be inferred that these people would run no matter what the weather was like.
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_run(e1) & in(x2,x3) & n_winter(x3) & n_marathon(x2) & n_people(x1) & n_quantity(x1))
exists e1 x1 x2 x3 x5.(n_weather(x5) & Theme(e1,x2) & Actor(e1,x1) & v_run(e1) & exists p1 x4.(n_thing(x4) & rel(x3,x4) & (x5 = x4)) & n_matter(x3) & rel(x2,x3) & n_marathon(x2) & n_people(x1))