Complex sentence: Jim and Maryann see the wreck and pick up the comatose Linda, taking her to hospital while behind them, the presence of the wrecked Trans Am on the freeway causes a multiple-car pileup.
Split into simpler sentences: Jim and Maryann see the wreck and pick up the comatose Linda, taking her to hospital. Behind them, the presence of the wrecked Trans Am on the freeway causes a multiple-car pileup.