In Piaget's preoperational stage, from about 2 to 6 or 7 years of age, children are learning to:

In Piaget's theory of cognitive development, the preoperational stage is characterized primarily by the development of language and symbolic thought, which occurs from approximately 2 to 6 or 7 years of age. During this phase, children start using words and images to represent objects and experiences, suggesting a growth in their communicative abilities.

However, while they are mastering language and can express their thoughts with increasing complexity, children in the preoperational stage struggle with understanding concrete logic. This means they often think in a very intuitive way that lacks the ability to consider multiple perspectives or understand the principles of cause and effect in a logical manner. Their reasoning is often based on appearances rather than a deep understanding of logical principles, such as conservation or classification.

Therefore, the correct answer highlights that children are learning to use language but do not yet have a solid grasp of concrete logic, reflecting the developmental milestones that characterize this specific cognitive stage.