Images are optional in some cases, but add greatly to the file size.

The new codes will be optional for six months and then mandatory beginning in November.

As before, the 3-speed automatic was optional in every model.

A lot of these are listed as optional in the protocol.

A leading zero is optional in practice (mostly not added).

The state is optional in both cases, but is typically used.

Elementary schools must have them, but they will now be optional in the upper grades.

The council office of marshal is optional in some jurisdictions.

Furthermore, live music became optional for the first time in the Contest's history.

Kindergarten is optional in most states, but few students skip this level.