No, there should not always be a comma after the word "hopefully." It depends on the sentence structure. When "hopefully" is at the beginning of a sentence, it is often followed by a comma, but if it is used within a sentence, a comma is not necessary.
Usually not, but it depends on context. There are no words that are always followed by a comma. You should concentrate on the use of verbs for a while.
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.
Not necessarily. Only use a comma when the final please is a request. For example, we say Do as you please; but Sit down, please.
You should have put the word 'or' in inverted commas, followed by a comma, or you might be misunderstood due to mistakes in punctuation!
Generally, no, unless the word "which" is followed by a parenthetical expression or phrase separated from the rest of the sentence by commas.
Yes, you should capitalize the word after a comma in a sentence.
"Inc" is not a word, it's an abbreviation for "Incorporated," and there should be a comma before it.
This will depend how the word "please" is used. Most sentences are unlikely to need a comma after the word, e.g. ""Please may I have a chocolate?" or "Please get me that book." However, a cmma could be used in some instances, e.g. "If you please, would you get me that book?"
No, it's not improper.
yes
No. There is no rule that a comma must always follow the word "which." In a parenthetical or appositive phrase, however, a comma may be required.Example:I did what I thought was right which, as I came to find out, was not.