1 The Portuguese explorer Vasco da Gama hadn't seen penguins before he travelled to South Africa in 1497. X
2 After he had made a pilgrimage to the city of Mecca in 1325, Ibn Battuta decided to become an explorer. ✓
3 Many explorers had tried to climb Mount Everest before Tenzing Norgay and Edmund Hillary reached the peak in 1953. ✓
4 People in Europe hadn't eaten potatoes until Christopher Columbus brought some from America. X
5 More than 400 years after Magellan had sailed around the world, the US submarine Triton made a similar journey underwater. ✓