挑战比试的英文表达是 "challenge test" 或 "challenge examination"。

来源：

这个短语是由两个单词组成的："challenge" 和 "test/examination"。"Challenge" 是一个名词，表示 "a call to engage in a contest, fight, or competition"（挑战）；"test" 和 "examination" 都是名词，表示 "a procedure or set of questions designed to evaluate the knowledge, skill, aptitude, physical fitness, or classification of someone or something"（测试，考试）。

例句：

He took the challenge test to see if he was ready for the real exam.（他参加了挑战比试，看看自己是否准备好参加真正的考试。）
She was nervous about the challenge examination, but she knew she had studied hard.（她对挑战比试感到紧张，但她知道自己学习很努力。）
The company offered a challenge test to all employees to see who had the best skills.（公司向所有员工提供了一次挑战比试，看看谁技能最强。）