甘草属于几级保护物种（）
A.1
B.2
C.3
D.4
E.不属于
参考答案：B
.
The best music teacher in the school has hurt his left foot and cannot ______ tomorrow’s concert.
A．take part
B．play a part in
C．participate in
D．participate
线路上钢轨硬弯应及时整正，用于60kg/m钢轨的调直机为YZ-2型，它是YZ-1型的改进。
