（）是能够连续跟踪特定目标并不断测量与输出目标坐标位置参数的雷达。
A、预警雷达
B、跟踪雷达
C、搜索雷达
D、火控雷达
参考答案：B
This bird is really lovely， and I’ve never seen ______ one.
A．a finer
B．a finest
C．the finer
D．the finest
– Alex, how long ____________ you ___________ in this school?
--For three years. I’ll graduate in July.
A．are; studying
B．do; study
C．will; study
D．have; studied
