The material on the canvas and the color process play an essential role.

"In times like this, they still play the essential role."

Both books deal with the essential role of justice in civic life.

Technology has played an essential role in the development of these products.

It once played an essential role in the black community.

Government spending has always played an essential role in market systems.

For their part, the drug companies say that the free samples play an essential role in the health care system.

Skiing played an essential role during the long winter months.

However, women also have an essential role to play in agriculture.

Member institutions play an essential role in the strength of the economy.