肺泡隔
参考答案：为相邻肺泡之间的薄层结缔组织，内含稠密的连续毛细血管和丰富的弹性纤维，还有少量的胶原纤维和网状纤维，具有良好的弹性和扩展性。
______this cake, you'll need 2 eggs, 175g sugar and 175g flour.
[ ]
A. Having made
B. Make
C. To make
D. Making
什么是PDCA循环，它有哪些特点？
