Complex sentence: The Portuguese invasion of Guinea in 1970 (known in Portuguese as "Operação Mar Verde"-Operation Green Sea) was a seaborne attack on the Conakry area of Guinea by 350 to 420 Portuguese soldiers and Portuguese-led Guinean fighters.
Split into simpler sentences: The Portuguese invasion of Guinea in 1970 is known in Portuguese as "Operação Mar Verde" (Operation Green Sea). The invasion was a seaborne attack on the Conakry area of Guinea by 350 to 420 Portuguese and Portuguese-led Guinean fighters.