sentences:  The Labour Party made a large win, gaining 10 seats and retained its place as the largest party and now had 53 seats in the House of Representatives.Den Uyl subsequently returned as a Member of the House of Representatives and as Parliamentary leader in the House of Representatives, taking office on 8 June 1977 but he was still serving in the cabinet and because of dualism customs in the constitutional convention of Dutch politics he couldn't serve a dual mandate he subsequently resigned as a Member of the House of Representatives and Parliamentary leader on 8 September 1977.Den Uyl was appointed as Formateur to form a new cabinet.