There are some (sitting)-room in the building 请问为什么用sitting，而不是sit sit为什么不用sitting呢，逗号后面不应该是非谓语吗，...

\uff08in\uff09the sitting room \u4e3a\u4ec0\u4e48\u7528in

\uff08in\uff09the sitting room
\u5f53\u8868\u793a\u4e00\u4e2a\u4eba\u6216\u7269\u4f53\u5904\u4e8e\u4e00\u4e2a\u6bd4\u5b83\u4eec\u5927\u5f88\u591a\u7684\u5c01\u95ed\u7a7a\u95f4\u91cc\uff0c\u7528\u4ecb\u8bcdin.\u8868\u793a \u5728\u3002
\u5982\u679c\u4e0d\u5f3a\u8c03\u5b83\u4eec\u5728\u7269\u7406\u7a7a\u95f4\u7684\u5177\u4f53\u4f4d\u7f6e\uff0c\u800c\u5f3a\u8c03\u5b83\u4eec\u5728\u4e00\u4e2a\u975e\u5b9e\u4e49,\u62bd\u8c61\u7a7a\u95f4\u7684\u4f4d\u7f6e\uff0c\u7528at.

\u662f\u5e76\u5217\uff0c\u4e3b\u8bed\u76f8\u540c\u65f6\u53ef\u7701\u7565\u3002\u8fd9\u91cc\u5b9e\u9645\u662fwe can sit\uff0c\u5f53\u7136\u7528\u539f\u5f62\u5566

sitting room

[英][ˈsitiŋ ru:m]
[美][ˈsɪtɪŋ rum]
n.起居室; 客厅;
表示起居室是一个固定搭配，自然不能用sit room. 另外起居室是一个名字短语是要用名词性结构的。

sitting是sit的动名词形式。 sitting room 客厅。名词词组

修饰名词room不可以动词，动名词是可以的。这叫动名词修饰名词，构成的整体是名词或者名词短语。

没啥。因为sitting-room是一个名词。

扩展阅读：i can sleep all day ... businessman ... there are some milk ... there are some birds ... which of the following ... there are some soup ... there are some fish ... there are some books ... there are so many ...