()是靠装配时的预压缩力和工作时的液压力使密封件产生弹性变形力来工作的。
A.密封圈密封
B.间隙密封
C.非接触式密封
D.焊接密封
参考答案:A
It's very nice _____ pictures for me. [ ]
A. of you to draw
B. for you to draw
C. for you drawing
D. of you drawing
简述《左传》在叙事上的特点。