Complex sentence: Twenty-four examples of class 71 (pre-TOPS type HA) were built in 1958 at the British Rail works in Doncaster, and in 1964 ten examples were deemed surplus to requirements, withdrawn from service and placed in storage.
Split into simpler sentences: Twenty-four examples of Class 71 were built in 1958 at the British Rail works in Doncaster. In the 1960s ten examples of Class 71 were deemed surplus to requirements and were withdrawn from service and placed in storage.