Complex sentence: The California Mountaineering Group is a grassroots mountaineering organization in the United States formed on June 1,2008 in California by a group of climbers dissatisfied with various other club models.
Split into simpler sentences: The California Mountaineering Group is a grassroots mountaineering organization in the United States. It was founded on June 1,2008 in California by a group of climbers dissatisfied with various other club models.