有效断面是平面.
参考答案：错
To live a green life, we try_________ more energy and produce less pollution.
A．to save
B．save
C．saves
D．saved
患儿风热郁肺，发热咽痛，伴有惊哭夜啼，治疗应首选（）
A.石膏
B.黄连
C.全蝎
D.蝉蜕
E.防风
