Complex sentence: Manitoba is far removed from the moderating influences of both mountain ranges and large bodies of water, and because of the generally flat landscape, it is exposed to cold Arctic high-pressure air masses from the northwest during January and February.
Split into simpler sentences: Manitoba is far removed from the moderating influences of either mountain ranges or large bodies of water. Because of the generally flat landscape, it is exposed to cold Arctic high-pressure air masses from the northwest during January and February.