Complex sentence: Regimental Police (RPs) are responsible for regimental discipline enforcement and unit custody in the British Army and some other Commonwealth armies who belong to the regiment or corps which they police instead of to the Royal Military Police or its equivalent.
Split into simpler sentences: Regimental Police (RPs) are soldiers responsible for regimental discipline enforcement and unit custody in the British Army and some other Commonwealth armies. They belong to the regiment or corps which they police instead of to the Royal Military Police or its equivalent.