A group of four men and to women are at a meeting and paying close attention to someone or something.
The people are in a meeting.
"Group of four men and two women" can also be stated as "people," as is sentence 2. "in" and "at" are interchangable prepositions in this case. "a meeting" is the direct object of both verbs. The primary difference is that sentence 1 has a conjunction and an additional sentence.
exists p1 s1 x1 x2 x3 x4.(exists e1 s2 x5 x6 x7 x8.(at(x1,x5) & subset_of(e1,x5) & (exists x9.(to(e1,x9) & n_person(x9)) | exists x10.(to(e1,x10) & n_thing(x10))) & Theme(e1,x8) & Actor(e1,x7) & v_pay(e1) & n_attention(x8) & a_close(s2) & Theme(s2,x8) & n_thing(x7) & subset_of(x6,x5) & n_meeting(x6)) & of(x1,x2) & n_woman(x4) & a_to(s1) & Theme(s1,x4) & n_man(x3) & subset_of(x4,x2) & subset_of(x3,x2) & card_eq_4(x2) & n_group(x1))
exists p1 x1.(n_people(x1) & exists x2.(in(x1,x2) & n_meeting(x2)))