Complex sentence: The Association of Southeast Asian Nations (ASEAN) reacted and signed Agreement on Transboundary Haze Pollution, formed a Regional Haze Action Plan (RHAP) and established a co-ordination and support unit (CSU).
Split into simpler sentences: The Association of Southeast Asian Nations (ASEAN) reacted. ASEAN formed a Regional Haze Action Plan (RHAP) and established a co-ordination and support unit (CSU).