In winter, the town by snow, so most of time we have to stay at home.
A：cut off
B：is cut off
C：cuts down
D：is cut down
在光线较弱的环境中使用显微镜观察时，应选用（ ）
都江堰建成之后，成为沃野，被称为“天府之国”的是（ ）
—Dr. Jackson is not in his office at the moment.
—All right. I____ him later.
