At the beginning of a sentence, you do not need to add a comma after "yesterday", "tomorrow", "today", "last week", "soon", etc.

Do not use a comma after "now" at the start of a sentence to describe when something happens.

At the beginning of a sentence, use a comma after the conjunctive adverb "instead" to indicate that it modifies the whole sentence that follows.

At the beginning of a sentence, we add a comma after the conjunctive adverbs "afterward", "then", "and then", "subsequently", "after that", or "later" to indicate that it modifies the complete sentence that follows.

Use a comma after "in particular" or "particularly" at the beginning of a sentence to modify (describe) a clause or a sentence. When modifying a single word, do not use a comma to separate "in particular" or "particularly" from the word it describes.

Add a comma after "in other words" to introduce a new sentence that repeats what has been said in a different way. "In other words" should be surrounded by commas in the middle of a sentence.

We use a comma after "finally", "eventually", or "in conclusion" at the beginning of a sentence to signal that these conjunctive adverbs modify the sentence that follows.

Add a comma after "similarly" or "likewise" at the start of a sentence. Do not use commas, however, when using "similarly" or "likewise" to modify a single word (adjective, verb, or adverb) in the middle of a sentence.

At the beginning of a sentence, transition words such as "moreover", "furthermore", "in addition", or "besides" should be preceded by a period or a semicolon and followed by a comma.