Short Answer 
A restrictive clause is essential to the meaning of a sentence, providing necessary detail about the noun it modifies without punctuation like commas. Key characteristics include having a subject and verb, and its removal alters the sentence’s meaning, as demonstrated in the example “The boy who I love to help is there.”
Step 1: Understand the Definition
A restrictive clause is a type of clause that provides essential information about the noun it modifies. Without this clause, the meaning of the sentence would change significantly. It functions to limit or specify which noun is being referred to.
Step 2: Identify Key Characteristics
To determine if a clause is restrictive, look for specific features:
- It must contain a subject and a verb.
- It should not be set apart by punctuation such as commas.
- It is essential for conveying the complete meaning of the sentence.
Step 3: Analyze an Example
Consider the sentence: “The boy who I love to help is there.” In this case, the clause “who I love to help” is restrictive because:
- It specifies which boy is being talked about.
- ‘I’ serves as the subject, and ‘help’ is the verb.
- Removing this clause would change the meaning or make it unclear.