The task of table structure recognition is  to recognize the internal structure of a table , which is a key step to make machines understand tables .
<meaning-changed> The task of table structure recognition is  to recognize the internal structure of a table , which is a key step to make machines understand tables .
The task of table structure recognition is an essential part for making machines understand tables. Its main task is to recognize the internal structure of a table , which is a key step to make machines understand tables .