【推荐1】上个月，下了一天的大雪后，操场盖上了厚厚的白雪。
After it snowed hard for a day last month, the playgrounds ________ snow.

【推荐2】看！白雪覆盖了大地。
Look! The ground is __________ __________ white snow.

【推荐3】His father covered the chicken with foil.(改为同义句)
The chicken ________ ________ ________ foil by his father.

【推荐1】在这些书卖完之前，你应该买一本。
You should buy one of the books before they are ________.

【推荐2】Mrs. Li hangs several paintings on the wall to make the office welcoming.（改为被动语态）
Several paintings ________ on the wall to make Mrs. Li’s office welcoming.

【推荐3】The government doesn’t allow people with no masks to take the underground in Shanghai.（改为被动语态）
People with no masks ________ ________ to take the underground in Shanghai.