在句子'孩子们在公园里玩耍'中，'在公园里玩耍'是谓语部分。

In the sentence 'The children are playing in the park,' 'are playing in the park' is the ___predicate.

他的研究预测睡眠质量与工作效率之间存在强相关性。

His research ___predicts a strong correlation between sleep quality and work efficiency.

他的理论建立在大量实验数据之上。

His theory is ___predicated on extensive experimental data.