Complex sentence: In March, German commander Erwin Rommel began his operations with a feinting advance, to test the British defenses; caught off-guard by his aggression and assuming the Germans were stronger than actuality, the Western desert force withdrew to Mersa El Brega.
Split into simpler sentences: In March, German commander Erwin Rommel began his operations with a feinting advance, to test the British defenses. Caught off-guard by his aggression and assuming the Germans were stronger than actuality, the Western desert force withdrew to Mersa El Brega.