Ⅰ.单词检测 1.______ vi.不同;相异 ___________ adv.不同地;相异地 2._____ adj.精确的;准确的 _______ adv.精确地;准确地 3.__________ adj.商业的;贸易的 4._________ vt.着手;从事;承担 _________过去式 __________过去分词
differ differently exact exactly commercial undertake undertook undertaken