Complex sentence: Beekeepers in Japan attempted to introduce the European honeybee in order to increase productivity, however, European honeybees have no defence against the hornet and the colonies are rapidly destroyed by these formidable insects.
Split into simpler sentences: Beekeepers in Japan attempted to introduce the European honeybee in order to increase productivity. However, European honeybees have no defence against the hornet and the colonies are rapidly destroyed by these formidable insects.