He also played a key role in most of the other new systems.
A strong focus on music in the family home also played a key role.
The foreign companies continued to play a key role in the oil industry.
We want to play a key role in the future.
Instead they had a key role to play in the attack.
If the Union takes a united stand, we can play a key role.
I believe that you have a key role to play here.
The first is the key role played by model building.
The paper played a key role in the campaign against the war for the next four years.
He played a key role in the development of the American film industry.