What's the name of the cloth you put on your chest when eating western steak?

The formal way is to press one corner of it under the plate, and the rest hangs down to cover the legs.

Or, fold diagonally to cover your legs.

No, the fort is in the collar.

When you leave the table halfway, fold it and put it on the seat. Knife and fork are placed on both sides of the plate in parallel, indicating that people will come back late.

Fold it and put it on the table after eating. At the same time, put the knife and fork in a figure of eight, indicating that it is over.