The Negro was draping a heavy, unclean-looking sheet over it and smoothing it down to form a lining to the box.

黑人正在用一张看起来很脏的厚床单盖住它， 然后把它弄平， 做成盒子的衬里。

Along with articular cartilage, another important component of synovial joints, and where they get their name from, is the synovium, which along with the surface of the articular cartilage, forms the inner lining of the joint space.

和关节软骨一样，滑膜是滑膜关节的另一重要组成成分，所以得名“滑膜关节”；滑膜分布在关节软骨的表面，形成关节腔的内层。