At as early as six months, the babies showed a preference for the helper over the hinderer.

这些婴儿最小的只有六个月，却已表现出对助人者的偏爱。

youdao

At as early as six months, the babies showed a preference for the helper over the hinderer.

这些婴儿最小的只有六个月，却已表现出对助人者的偏爱。

youdao