"Which" is used to provide additional, nonessential information in a sentence, set apart by commas. "That" is used to provide essential information, without commas, and is critical to the sentence's meaning.
You use "which" if it is something nonessential to the sentence, and you use "that" when it is essential. Anything with a "which" should be set off by commas, but anything with a "that" should not. Examples: The dinner, which was quite tasty, was not very long. The dinner that we had at Wendy's was not very elegant.
The non-essential subordinate clause is marked off by two commas, which act as a pair of parentheses. 'My cousin is a doctor' (independent clause). 'My cousin, who lives in Manchester, is a doctor' (non-essential subordinate clause; the information 'who lives in Manchester' is merely descriptive). 'My cousin who lives in Manchester is a doctor' (essential subordinate clause; the information 'who lives in Manchester' distinguishes this cousin from my other cousins who live elsewhere, therefore there are no commas).
essential means it is very important and nonessential means that it isn't important.
Not essential., A thing not essential.
Parenthetical phrases should be set off by commas if they provide additional, nonessential information within a sentence. If the information is essential to the meaning, do not use commas. It's important to maintain consistency in your punctuation usage for clarity and readability.
Commas are used in punctuation to separate items in a list, connect independent clauses in a sentence, set off introductory or nonessential phrases, and clarify the meaning of a sentence by indicating pauses or divisions in the text.
You use commas when your writing a list of things like fruit names. You would not just leave it like this apple orange grapes and pear. You would rather use commas like this apple, orange, grapes and pear.
WHO ARE NON-ESSENTIAL WORKERS
Glycine is a nonessential amino acid, which means that the body can produce it on its own and it is not required to be obtained from the diet.
Commas are used to separate items in a list, set off introductory phrases or clauses, separate independent clauses in a compound sentence, and set off nonessential information in a sentence.
Commas are used to separate items in a list, to separate independent clauses in a compound sentence, to set off introductory phrases or clauses, and to offset nonessential information.