Syntactic analysis focuses on the grammatical structure of a sentence, ensuring it adheres to the rules of syntax. It breaks sentences into parts like phrases and clauses, creating parse trees that represent hierarchical relationships. For instance, in the sentence "The dog barked loudly," syntactic analysis identifies "The dog" as a noun phrase and "barked loudly" as a verb phrase. This analysis helps NLP systems understand how words relate to each other within a sentence.
Semantic analysis, on the other hand, delves into the meaning of the sentence. It interprets the relationships between words, disambiguates meanings, and derives logical representations of the text. For example, semantic analysis ensures that "The bank is next to the river" refers to a financial institution, not the edge of a river, by considering context. While syntax ensures grammatical correctness, semantics ensures meaningful interpretation.
Both syntactic and semantic analyses are crucial for NLP applications. Syntax helps in tasks like grammar checking and dependency parsing, while semantics aids in understanding intent, question answering, and machine translation. Combining both analyses allows NLP systems to generate accurate and context-aware outputs, particularly in tasks requiring deep understanding, such as chatbots or summarization.