Looking on the internet deeply has found these results:

be of great help for is the most popular phrase on the web.

be of great help fo 1192 results on the web	be of great help for 1386,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
I can be of great help. An item belonging to the deceased would be of great help. I think they can be of great help. While the words can be of great help. Colonel Sheppard believes you can be of great help to us. Better police training in this field would be of great help. I know I can be of great help to the ship. This will be of great help to the Ukrainians.	I think they can be of great help. LAC Summit, and I believe that it will be of great help for the preparation and conduct of the summit meeting. Better police training in this field would be of great help. This solution will be of great help to, for example, the candidate countries in Central and Eastern Europe which have been in some doubt as to what they should do. I can be of great help. I have listened very carefully to the debate on the preparations for the EU Colonel Sheppard believes you can be of great help to us. While the words can be of great help.

be of great help fo

1192 results on the web

be of great help for

1386,000 results on the web

More popular!

I think they can be of great help.
LAC Summit, and I believe that it will be of great help for the preparation and conduct of the summit meeting.
Better police training in this field would be of great help.
This solution will be of great help to, for example, the candidate countries in Central and Eastern Europe which have been in some doubt as to what they should do.
I can be of great help.
I have listened very carefully to the debate on the preparations for the EU
Colonel Sheppard believes you can be of great help to us.
While the words can be of great help.