Hi Anis,

> If there are some sketch appear, the prompt should be :
> select sketch, edge or faces to fillet.

No, that's probably not a good idea since it is also possible to select whole objects as well.

For example draw a solid box, then select the box (no edges or face sub-object selection, just the whole box by a single click) and you can now run Fillet to round all edges of the box.

In Fillet you can select either 2 separate curves, or a multi-segment curve, or edges, or faces, or 2 independent surfaces, or an entire multi-surface joined object.

That's a lot of different things, it would make the prompt too long.

If you need to do a lot of filleting it is better to just make sure to learn how it works.

If you need a reminder, this behavior is covered in the Fillet entry in the help file:
http://moi3d.com/1.0/docs/moi_command_reference7.htm#Construct_Fillet

- Michael