endosteum的复数形式怎么拼写？

endosteum的音标：endosteum的英式发音音标为：[en'dɒstɪəm]endosteum的美式发音音标为：[en'dɒstɪrm]...

The new bone that closed the marrow cavity could only be formed by the endosteum.结论关闭髓腔的骨质只能来自于骨内膜成骨....

n.骨内膜...