Yes, it is common to use a comma after the word "upon" when it is used at the beginning of a sentence to introduce a new idea or point. For example: "Upon arriving at the airport, we realized our flight was delayed."
No.
You can put a comma before or after just about any word if the sentence structure requires it. If the sentence structure does not require it, it may be permissable to use a comma to assist in clarity and avoid confusion. Otherwise, don't use a comma. Have I confused you yet? Using a comma does not depend on the word, it depends on the structure of the sentence.
It is not proper to use a comma after the word "thanks" in the phrase "thanks again."
"Therefore" is a transitional word and traditionally a comma is placed after the word to indicate the transition. For example: The economy of the United States was historically based upon agriculture; therefore, a proposed tariff on exported cotton was extremely unpopular with Congress.
No, a comma is not typically used before the word "apparently" at the end of a sentence.
No. After the word and comma can not be used, as it is grammatically inappropriate to use comma after conjunctions such as and, which are called coordinate conjunctions.
You can, depending on the context.For example: Upon returning to my house, I discovered I had left the stove on.
There is no word in English that necessarily requires a comma.
NO
Not necessarily. There is no word in English that requires a comma.
no
No
no
no
no
No.
In many cases, the word 'however' is followed by a comma. The problem with the word is that one must be careful not to over use a comma. However the word is used,(note that there is no comma used in this connection) the word itself frequently does not need a comma as an automatic punctuation.However, (meaning 'on the other hand') phrasing will most often determine if the word is followed by a comma. These two instances here are examples of when to use or not use the comma as punctuation for this word. When the word is used as a substitute for the phrase 'on the other hand', it is most often followed by a comma.