这位经济学家是一位坚定的试验主义者，主张在全面改革前先进行区域性测试。

The economist is a dedicated ___trialist, advocating for regional testing before full-scale reforms.

我们的乐团很幸运有一位能熟练演奏小提琴、吉他和钢琴的三乐器演奏家。

Our orchestra is lucky to have a ___trialist who plays violin, guitar, and piano expertly.

这位铁人三项选手在三个赛段中都保持了稳定的配速。

The ___trialist maintained a steady pace throughout all three stages of the race.