A teenager in a red shirt is skating on a skateboard at a skate park.
A young kid is trying to freshen up on his skateboarding skills.
A young kid and a teenager are not the same thing. It doesn't imply that the teen is trying to freshen up his skateboarding skills.
exists e1 s1 x1 x2 x3 x4 x5.(at(e1,x4) & n_park(x4) & of(x4,x5) & n_skate(x5) & on(e1,x3) & n_skateboard(x3) & Actor(e1,x1) & v_skate(e1) & in(x1,x2) & n_shirt(x2) & a_red(s1) & Theme(s1,x2) & n_teenager(x1))
exists e3 e1 p1 s1 x1 x2.(Topic(e1,p1) & Actor(e1,x1) & v_try(e1) & exists e2 s2.(a_up(s2) & Manner(e2,s2) & on(e2,x2) & Actor(e2,x1) & v_freshen(e2)) & n_skill(x2) & Actor(e3,x2) & v_skateboard(e3) & of(x2,x1) & n_male(x1) & n_kid(x1) & a_young(s1) & Theme(s1,x1))