The correct sentence would be "He could not have been there". This is because 'can' is in the present tense and doesn't agree with the rest of the sentence.
It depends on what you're trying to say. If you had the possibility of being a doctor, you could have been a doctor. If it was in your best interest to be a doctor, you should have been a doctor. Or if you're trying to distinguish between "could of" and "could have", it should be, you could have been a doctor.
Both could be correct. One is a question - How long have you been playing tennis? One is a statement - You have been playing tennis.
"Have been" is the correct phrase to use. "Have being" is not grammatically correct.
Yes it's polite and considering towards the receiving party.
The correct phrase is "I could have." "Could of" is incorrect and a common spelling mistake, as it sounds like "could've" when spoken due to contraction with "have."
"You could not have been" is grammatically correct. "You could not have been at the cinema last night, because I saw you in the park."
NO. These are correct; I could have punched I have punched I had punched I had been punched I have been punching I had been punching
Was/were there, depending on the subject.I was thereWe were thereYou were thereHe/She/It was thereThey were there
It depends on what you're trying to say. If you had the possibility of being a doctor, you could have been a doctor. If it was in your best interest to be a doctor, you should have been a doctor. Or if you're trying to distinguish between "could of" and "could have", it should be, you could have been a doctor.
That is correct. You could also say: Tom has been unemployed for a month.
You have been travelling is correct. You would never say you have been on travelling, although for poetic emphasis you could say you have been travelling on.
I could not be more proud
Been is the past tense of the verb to be: I have been to the library. The term "of been" is not a correct phrase in English. Unfortunately, many people use it instead of "have been". For example, "I could of been an athlete." is incorrect; "I could have been an athlete." is the correct term.
Both could be correct. One is a question - How long have you been playing tennis? One is a statement - You have been playing tennis.
"Have been" is the correct phrase to use. "Have being" is not grammatically correct.
It is correct to use "have" with the plural subject "you and your family". For a correct sentence, you could say, "I hope you and your family have a nice evening."
Yes it's polite and considering towards the receiving party.