重 点
You use unless to introduce the only circumstances in which an event you are mentioning will not take place or in which a statement you are making is not true. 除非; 如果不
conjunction [推进连词] 除非，除非在…情况下；若非，如果不
We cannot understand disease unless we understand the person who has the disease. 除非我们了解有某种疾病的人，否则我们不会了解疾病。
preposition [方式和原因] 除…之外；除…之外
I won't tell them—not unless you say I can. 我绝不告诉他们—除非你允许。
后缀: less
【adjective】 表示缺乏或没有某种特性 - indicating the absence or lack of a particular quality
原词: unless
是通过后缀 【less】 构成的派生词
- unless 出现在下面的课文中（提供视频、音频及笔记等可系统性学习）
- Lesson 1 A puma at large
- Lesson 6 The sporting spirit
- Lesson 28 Patients and doctors
- Lesson 34 Adolescence
- Lesson 37 The process of ageing
- Lesson 38 Water and the traveller
