difficult

These are very testing times for our family. 这些日子是我们家极其困难的时期。

This testing circuit is a challenge for any racing driver. 这个测试车场对任何赛车手都是个挑战。

the act or practice of giving tests to measure someone's knowledge or ability

Statewide testing begins this fall. 全国考试从今年秋天开始。