The sentence that will help explain Alice's current predicament is: “This must be the wood,” she said thoughtfully to herself, “where things have no names.”
This line directly relates to Alice's confusion regarding the word for the tree. It indicates that she is in a place where the usual logic and naming conventions do not apply, contributing to her struggle to remember who she is and the inability to identify the tree. This context clarifies why she is perplexed and unable to recall the word she is searching for, emphasizing the nonsensical and whimsical nature of the environment she is navigating.