unless如何理解在整句? 断句: 1、In general therefore valves tend to 2 and 3. 2、be Nickel or copper based materials 3、 unless the pressure differential is less than 1 barg a pipe section 10X diameter is also required in a nickel or copper based material both upstream and downstream of the valve position. 1是主句,2、3是and连接的宾语,其中3是宾语从句。 对3进行断句unless the pressure differential is less than 1 barg是状语从句,a pipe section 10X diameter is also required in a nickel or copper based material both upstream and downstream of the valve position. 是该宾语从句的主体。 这样断句后进行翻译就简单了,译文基本与3楼相同。查看更多