Only if it is the first word in a sentence.
All proper nouns start with a capital letter.
Sierra, since its a name and thus a proper noun it should start with a capital letter.
If it's at the start of a sentence - yes, otherwise - no.
No, but you need to use a capital letter to start the sentence, and the word English also begins with a capital letter.
Capital letters are a convention, or custom, that help readers become oriented in a text. The first word in a sentence begins with a capital letter. To an experienced reader in English, in the first word in a sentence, the capital letter signals that a new complete thought is being started with that new sentence. Capital letters also signal something special or unique. We capitalize the first letter of unique people, places, things, and ideas. While there is no inherent reason that we should use capital letters to signal these ideas, there are agreed-upon rules or "conventions" (customs) that we use to make reading faster, smoother, and more meaningful.
The words that should start with a capital letter are places, names, important words in a title, and the letter at the start of a sentence.
No Only names of people or places etc have capital letter at start
Yes, all books start with a capital letter.
No it won't, unless it is at the start of a sentence.
Yes it should.
It should start with a capital letter at the beginning of a sentence because it is n ot a proper n ou n.
Yes, "Best wishes" at the end of a letter should start with a capital letter.
Yes - all planets names begin with a capital letter.
no. its not a place, it not a person, and it should not be a capital letter.
not if it doesn't start a sentence.
No, there should not be a capital letter after an exclamation mark. After an exclamation mark, you should start the next sentence with a lowercase letter unless it is a proper noun.
Colors do not need a capital letter unless it is part of a Title. e.g. The Red Badge of Courage (a book)