不可数。

比如同类词，你类比一下：understanding 名词 n. [U]1.了解;理解;领会;认识I doubt whether he had any real understanding of Shakespeare. 我怀疑他是否真正理解莎士比亚的作品。

2.理解力;判断力The problem is beyond my understanding. 这个问题我无法理解。

3.谅解;协议;共议[S1][(+with)][+that]We came to an understanding after the argument. 经过争辩以后,我们达成了谅解。

4.同情心,同感;融洽[S1]She showed great love and understanding. 她表现出极大的爱和同情。