Final answer:
To distinguish between a predicate adjective and a predicate noun, identify the linking verb in the sentence and determine if the word following it is an adjective describing the subject (predicate adjective) or a noun renaming the subject (predicate noun).
Step-by-step explanation:
To determine whether a sentence contains a predicate adjective or a predicate noun, it's important to understand the parts of the sentence. The predicate of a sentence is the part that states something about the subject and includes the verb. When the predicate includes an adjective directly following a linking verb such as 'is' or 'seems' that describes the subject, it is called a predicate adjective. For example, in 'The sky is blue,' 'blue' is a predicate adjective describing 'the sky.' On the other hand, a predicate noun, also known as a subject complement, follows a linking verb and renames or identifies the subject. For instance, in 'Sandra is a doctor,' 'doctor' is a predicate noun that renames 'Sandra.' To identify these components within a sentence, one should look for a linking verb and then determine if the word following it describes or renames the subject.
Lastly, adjectives and nouns aren't the only important parts of speech that can be part of a predicate; verbs, adverbs, and even entire phrases can also enhance the meaning and detail of a sentence. Recognizing these elements within a sentence can help with understanding the grammar and syntax, thus improving communication skills.