1. An insect is a small creature, that has six legs.
2. An insect is a small creature that has six legs.
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Which one is grammatical?
Is #1 wrong in terms of grammar?
Can we put 'comma' before 'that' as in Sentence 1?
#2 is correct. No comma is needed because "that" introduces an essential clause.
http://grammar.ccc.commnet.edu/grammar/clauses.htm#independent
Essential clauses and Restrictive clauses are two terms for the same thing!
Both sentences 1 and 2 are grammatically correct, but they have slightly different punctuation.
In sentence 1, there is a comma before the relative pronoun "that." This is called a "comma splice" and is incorrect in standard written English. Therefore, sentence 1 is incorrect in terms of grammar.
Sentence 2 is correct. There is no comma before "that," which is the preferred punctuation in this case.
So, to answer your question, no, we cannot put a comma before "that" in sentence 1. The correct punctuation in sentence 2 is the absence of a comma before "that."
Both sentence 1 and sentence 2 are grammatically correct.
Sentence 1: "An insect is a small creature, that has six legs."
Sentence 2: "An insect is a small creature that has six legs."
The main difference between the two sentences is the presence of a comma before the word "that" in sentence 1. In this case, the comma is used to create a pause and can be seen as an optional stylistic choice.
From a grammatical perspective, both sentences convey the same meaning and are acceptable. Sentence 2 is more commonly used in formal writing, while sentence 1 is often used in informal or creative writing to add a slight pause and emphasis before the clause "that has six legs."
So, while sentence 1 is not grammatically wrong, it is less common and might not conform to stricter grammatical style guidelines.