A thermoplastic bag may include a sidewall that may have a plurality of first and second ribs formed therein. The first ribs may be longer in length but shorter in height than the second ribs. The second ribs may be arranged in discrete networks that appear superimposed over the first ribs. The second ribs may normally remain in a bent-over configuration. When a force is applied, the second ribs may expand the area of the sidewall so that the bag may easily accommodate large objects. To produce the bag, a thermoplastic web may be directed between opposing first and second rollers. One of the rollers may include ridges that may have first and second segments of differing heights that correspond to the differing heights of the first and second ribs. The formation of the first ribs may increase the width of the web.