当其他狗靠近时，这只小狗变得更好斗了。

The puppy got ___feistier when other dogs approached.

尽管年纪大了，她依然是辩论俱乐部里最斗志昂扬的成员。

Despite her age, she remains the ___feistiest member of the debate club.

那只小狗变得越来越爱叫了，稍有点动静就狂吠不止。

The little dog has been getting ___feistier, barking loudly at the slightest noise.