孩子们在游乐场玩得很开心。

The kids seem much ___happier playing at the playground.

她收到礼物后看起来更开心了。

She looked ___happier after receiving the gift.

我们在同一时间到达机场真是个幸运的巧合。

It was a ___happier accident that we arrived at the airport at the same time.