Complex sentence: Epic battle of the First Balkan War of 1912 during which the Serbian forces of Field Marchal Radomir Putnik crushed the Ottoman army of General Zekki north of Uskub, known today as Skopje, the modern capital of Macedonia.
Split into simpler sentences: Epic battle of the First Balkan War of 1912, during which Serbian forces under the command of Field Marshal Radomir Putnik crushed the Ottoman army of General Zekki. The battle occurred north of Uskub, which is today known as Skopje, the modern capital of Macedonia.