Once ____________ ,  a plan should be carried out.

Nowadays people sometimes separate their waste to make it easier for it ______.      .

  ________ the city center, we saw a stone statue of about 10 meters in height.(2010·上海)

Paul doesn’t have to be made ____. He always works hard.

To make believe that there was still someone in the house, the housewife went downstairs, ______ the lights ______ in the living room.