challenge的形容詞詞

It is not just readers who are challenging the media elite.

挑戰媒體精英的不僅僅是讀者。

Once upon a time the physical book was a challenging thing.

從前，實體書是一件具有挑戰性的`東西。

Killy began challenging the basic theories of racing technique.

基利開始挑戰賽車技術的基本理論。