Question

【題目】____ you start eating in a healthier way, weight control will become much easier．

A. Unless B. Although

C. Before D. Once

Answer 1

【答案】D

【解析】試題分析：句意：一旦你開始更健康的飲食，控制體重就會變得容易得多。unless除非；although盡管；before 在……之前；once 一旦。unless相當(dāng)于if not，引導(dǎo)條件狀語從句；although引導(dǎo)讓步狀語從句，不能和but連用；before引導(dǎo)時間狀語從句；once引導(dǎo)具有條件意味的時間狀語從句。根據(jù)語境和詞義可知選D。