A skateboarder jumps off his skateboard in midair in hopes of landing back on it.
A skateboarder happily jumps.
No indication that he/she is happily jumping anything. Could be just jumping.
exists e1 e2 s1 s2 x1 x2 x3 x4 x5.(in(e1,x4) & a_back(s2) & Manner(e2,s2) & on(e2,x1) & n_thing(x1) & Actor(e2,x5) & v_land(e2) & (x4 = x5) & n_hope(x4) & a_off(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_jump(e1) & in(x2,x3) & n_midair(x3) & n_skateboard(x2) & of(x2,x1) & n_male(x1) & n_skateboarder(x1))
exists e1 s1 x1.(a_happily(s1) & Manner(e1,s1) & Actor(e1,x1) & v_jump(e1) & n_skateboarder(x1))