The country's official languages are Comorian and French, though most Comorans do not speak or write French. Land and climate. Most of the Comoro Islands were formed by volcanoes. Mont Kartala, a volcano on Grande Comore, is still active. Plateaus and valleys lie below the volcanic peaks.
Mangrove swamps form the shorelines of almost all the islands.
Some of the islands have dense forests. However, much forestland has been cleared for farming. Such clearing has resulted in severe soil erosion on most of the islands. Comoros has a cool, dry climate from May through October. A hot, rainy season lasts from November through April.