VERBS | ADVERB | PREPOSITIONVERBS➤be是補充ADVERB➤essentially必要補充▸➤mutually相互補充◇These two aims are not always mutually complementary: at times they conflict.這兩個目標不總是互補的:有時它們相互抵觸。PREPOSITION➤to對⋯是補充◇We provide a service that is essentially complementary to that of the banks.我們提供的服務是對銀行服務的必要補充。