lubricating

1.The pleurae are serous membranes, which mean they secrete a lubricating fluid, called serous fluid.

胸膜为膜，这意味着它们可以分泌液，液。

2.1. the backbone fault of the nappe tectonic was not “F.2”, but within the anhydrite member underlaid the nappe, and the anhydrock was an ideal lubricating layer;

推覆构造的主干断层不是F_2,而是在推覆之下的硬石膏段中,硬石膏岩是理想的层;