Complex sentence: It was formerly two islands, namely Da Hengqin (Portuguese: D. João) and Xiao Hengqin (Montanha), which very recently connected by land reclamation.
Split into simpler sentences: It was formerly two islands, namely Da Hengqin (Portuguese: D. João) and Xiao Hengqin (Montanha). The two islands were very recently connected by land reclamation.