Complex sentence: The EUMS is led by the Director General (DGEUMS, a three-star general) who is assisted by the Deputy Director General and the Chef of Staff (DDG/COS, a two-star general/Rear Admiral).
Split into simpler sentences: The EUMS is led by the Director General (DGEUMS, a three-star general). DGEUMS is assisted by the Deputy Director General and the Chef of Staff (DDG/COS, a two-star general/Rear Admiral).