The primary challenge of the wooden round requirement was to design the engine to be as reliable as possible.

His primary challenge will be taking a government with a large indebtness and high deficit.

In that respect, the primary challenge of the modern age consisted in finding a method to keep the human touch attached to the products.

He endured a tough primary challenge during his first campaign, before winning the general election by an 8-point margin.

He lost a primary challenge in 2004, and lost another primary in 2006.