A challenge

挑试───A challenge

You can rely on him to respond to a challenge.───你可以信赖他，他懂得应付挑战。

I called out a challenge, but there was no reply.───我发起了一个挑战，但是没人回应。

Taking her with me on official occasions has been a challenge.───在正式场合带上她对我而言是一种挑战。

Extensive operating costs and marginal advertising revenue in the economic downturn have made it a challenge for YouTube to turn a profit.───在经济低迷的时期，巨额的运营成本以及微薄的广告收入使得YouTube盈利面临着巨大的挑战。

The problem is a challenge set up by the entity for one of its own personalities, but the outcome is up to the personality involved.───这难题是实体为它自己的某个人格而设置的挑战，而其结果也与这个人格有关。

It was more of a challenge to preserve it once brought to the surface because of the change in pressure, he added.───他指出，一旦拿出水面，由于压力变化，要保存这些酒就会面临更大的挑战。

She beat off a challenge to her leadership.

He threw out a challenge.

I always relish a challenge.

She likes her job to be a challenge.

I see the job as a challenge.