Complex sentence: As of 2013, massive hydraulic fracturing is being applied on a commercial scale to shales in the United States, Canada, and China; in addition, several countries are planning to use hydraulic fracturing for unconventional oil and gas production.
Split into simpler sentences: As of 2013, massive hydraulic fracturing is being applied on a commercial scale to shales in the United States, Canada, and China. Several countries are planning to use hydraulic fracturing for unconventional oil and gas production.