Complex sentence: On 1 August, Hitler issued Directive 17, extending "Luftwaffe" operations to the British mainland and RAF-related targets and on "Adlertag" (Eagle Day, 13 August) the main air offensive against the RAF began.
Split into simpler sentences: On 1 August, Hitler issued Directive 17, extending "Luftwaffe" operations to the British mainland and RAF-related targets. On "Adlertag" (Eagle Day, 13 August) the main air offensive against the RAF began.