Question

【题目】In 1620, about half the USA forests.

A. was covered B. covered with

C. were filled with D. was covered with

Answer 1

【答案】D

【解析】考查被动语态和句意理解。句意：1920年，美国一半的土地都被树林覆盖。cover sth. with sth意为“用……覆盖……”。about half the USA和cover之间是被动关系，故该句应用被动语态，故D选项正确。