Câu 1:
a) the workers cleaned the streets last night
=> the streets..............................................
b) They will know the result next week.
=> The result............................................
c) We should use cloth bags intstead of  plastic bags.
=> Cloth bags............................................................
d) The farmers have recycled the waste for thousands of year.
=> The waste.....................................................................
e) He is collecting drink cans for recycling.
=> Drink cans........................................................
f) people can recycle tire to make pipes or floor covering.
=> tire.................................................................
g) the government made a new law several years ago.
=> a new law.........................................................