Adjective modifier

• first: On 6th December 1909 the company stating operating it's first gasoline motorbuses to areas of the town not covered by the tramways.

Modifies a noun

• service: Mr. Bradney William's car was, in 1901 he had started Bexhill's first motorbus service.

• operation: In 1954, London Transport announced that it was their intention to convert all trolleybus routes to motorbus operation from the late 1950's.