to strive; to struggle

I fight for my family.

They are struggling with the goal of wiping out smallpox.

The most important thing in the Olympic Games is not to win but to take part, just as the most important thing in life is not the triumph but the struggle. The essential thing is not to have conquered but to have fought well.

We were founded upon the ideal that all are created equal, and we have shed blood and struggled for centuries to give meaning to those words – within our borders, and around the world.

I have to fight.