孩子们在操场上打棒球。

The kids are playing ___baseball on the playground.

孩子们在后院打棒球时丢了一个棒球。

The kids lost a ___baseball while playing in the backyard.

孩子们在田野里打棒球，不小心把球打过了围栏。

The kids were playing in the field and accidentally hit the ___baseball over the fence.