Several extensions to the system are currently under construction or have been proposed.

Many extensions to the base protocol have been proposed and are in common use.

More than 100,000 people used the service within the first 12 months and an extension to Leicester was proposed.

An extension was proposed and completed in 1888 providing another 266 seats.

Various other extensions, including entirely new lines, have been proposed but not yet approved.

At various times other lines and extensions were proposed, but none came to anything.

This extension has been proposed in various forms for over 80 years.

A further extension of the reserve to include areas in Liberia has also been proposed.

I cannot see a reason, therefore, why a further extension for this measure should be proposed.

In the very east another extension is proposed to Golyanovo.