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】句意：一旦你開始更健康的飲食，控制體重就會(huì)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(shí)間狀語從句；once引導(dǎo)具有條件意味的時(shí)間狀語從句。根據(jù)語境和詞義可知選D。