每个系动词应写在那些名词之后？

不太懂你的意思。

am, is, are 可以跟在任何单词之后。
例如
1、跟在代词后：I am a boy.
The apple that I give to you is red.
2、跟在名词之后：The apple is good.
3、跟在动词之后：The car that I drive is red.
4、跟在形容词之后：The apple that is green and gradually becomes red is mine.
总而言之，系动词的形式与它前面的单词没有关系，与主语和句子的时态有关系。想要确定系动词，应该寻找主语。