下列()的种子可借助果实开裂时的弹力散播。
A、榆树
B、凤仙花
C、莲蓬
D、山蚂蝗
参考答案:B
Are they talking _______ the teacher _______ the weather? [ ]
A. with, in
B. with, about
C. about, with
浇筑完的无砟轨道支承层在()内不得受冻。
A、3
B、7
C、14