People gathered around a hot air balloon in the process of inflating.
A group is watching as a hot air balloon fills up.
Hot air balloon fills up is rephrasing hot air balloon inflating.
exists e1 s1 x1 x2 x3 x4 x5.(n_process(x4) & in(e1,x4) & of(x4,x5) & n_inflate(x5) & around(e1,x2) & n_balloon(x2) & of(x2,x3) & n_air(x3) & a_hot(s1) & Theme(s1,x2) & Actor(e1,x1) & v_gather(e1) & n_people(x1))
exists e1 p1 x1.(exists e2 s1 s2 x2 x3.(a_up(s2) & Manner(e2,s2) & Actor(e2,x2) & v_fill(e2) & n_balloon(x2) & of(x2,x3) & n_air(x3) & a_hot(s1) & Theme(s1,x2)) & as(e1,p1) & Actor(e1,x1) & v_watch(e1) & n_group(x1))