Some people are walking down the sidewalk in a city.
A man and woman are holding hands while walking down the sidewalk  in a city.
Some people does not need to mean specifically a man and a woman. People can walk down the sidewalk in a city without holding hands.
exists e1 x1 x2 x3.(n_sidewalk(x2) & down(e1,x2) & in(x2,x3) & n_city(x3) & Actor(e1,x1) & v_walk(e1) & n_people(x1))
exists e2 e1 s1 x1 x2 x3 x4 x5 x6.(n_sidewalk(x5) & while(e1,e2) & in(e2,x6) & n_city(x6) & a_down(s1) & Manner(e2,s1) & Theme(e2,x5) & Actor(e2,x1) & v_walk(e2) & Theme(e1,x4) & Actor(e1,x1) & v_hold(e1) & n_hand(x4) & n_woman(x3) & n_man(x2) & subset_of(x3,x1) & subset_of(x2,x1))