A man in a long-sleeved shirt, riding a yellow moped across a street.
a man rides a moped for the first time
The man riding the moped could be riding at any time, nothing implies that the man is riding for the first time.
exists e1 s1 s2 x1 x2 x3 x4 x5.(a_topic(x1) & across(e1,x5) & n_street(x5) & Theme(e1,x4) & Actor(e1,x3) & v_ride(e1) & n_moped(x4) & a_yellow(s2) & Theme(s2,x4) & (x1 = x3) & in(x1,x2) & n_shirt(x2) & a_long-sleeved(s1) & Theme(s1,x2) & n_man(x1))
exists e1 s1 x1 x2 x3.(n_time(x3) & a_first(s1) & Theme(s1,x3) & Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & for(x2,x3) & n_mope(x2) & n_man(x1))