Câu hỏi:

 In Britain, the milkmen (1) ________ bottles of milk to houses and collect the empty ones. The empty bottles are then cleaned and refilled. Every milk bottle can be reused thirty times. People throw (2) ________ billions of cans every year all over the world. In Oregon, the government made a new law several years ago. They said that there must be a (3) ________ on all drink cans. The deposit is (4) ________ when people bring the cans back for recycling

In Britain, the milkmen (1) ________ bottles of milk to houses and collect the empty ones.