Hello aspirant. Grace Marks are like, when an answer is not apt to the question, certain Marks would be given or when an answer is only relatable to certain extent, then some Marks would be given. In such cases, Marks are said to be grace Marks. Ofcourse in hsc,  grace marks would be given. Not only for English or commerce in specific. For any subject, grace Marks would be given in boards. But the mark would be dependent on who corrects your paper.

For example, if reasonably strict person corrects your paper

If the question is for 10 mark in english. And you write the apt answer.

He would give you 8 or 9

If your answer is 50 to 70 percent relatable, then he would give you 6 or 7

If only answer is there that is just written to attempt,

Then he would give you 3 to 4 Marks

This is grace mark

Hope this helps

Regards

Nikhitha