Try a 50 minute mock examination, and know just how good you really are.

In order to continue to challenge new things, in order to meet new needs, we work day in day out in R&D.

The prime minister directly confronted the challenges of his political opponents.

She stood defiantly with arms akimbo.

I'm ready whenever they challenge me.

He shouted defiance at me.

He challenged the mountain at the risk of his life.

He encouraged me to try again.

However hard he may try, he won't succeed.

He often takes a defiant attitude toward us.

He's mowed down a parade of challengers before.

One of the important differences between Japanese and Americans is that Japanese tend to choose a safe course in life, while Americans choose to explore and challenge life.

He looked the toughest of all the challengers.

Thirdly, if you don't put in the effort and challenge difficult things, there is nothing in the world at which you will succeed.

I am going to establish a new world record for swimming.

I tried the problem again and again.

I took a chance and accepted his challenge.

He's reigning champion, and no young challenger is going to take it away from him.

My brother tried many times to pass the examination, finally succeeding.

I got my driver's license on the second time I tried to pass the driver's test.