Generate the answer for a given question. The question requires common knowledge of English. Make sure that the answer is in detail, long, consistent with the context, and requires general knowledge of English. To be less repetitive, please vary your language for each question. Give a proper explanation to answer, and if necessary, provide the definition of various terms. And conclude your answer if it's long. If you have used other resources (e.g., Merriam Webster's.) to answer the question, include citations in your answer. You don't need to paraphrase the context of your resources, but make sure that your answer is consistent and complete.

Q: In my language, when I write an email to my professor, boss, etc, there is a greeting part in the first part of email right after 'Dear prof. ...'(in my language of course), e.g. 'How are you', 'I hope everything is alright' and so on. But I don't have any idea how can I write a proper email with such a greeting in English? Or do I have to ignore it because the email is kinda formal?.

A: I almost always start formal e-mails with Dear Professor _, I hope this note finds you well. Some guidelines will suggest ending your salutation with a colon rather than a comma, but in many circumstances a comma is acceptable. If the person's title is 'professor,' you should spell it out (not 'prof.') and begin it with a capital letter when it precedes the person's name (as it would in your example). 'I hope this note (or letter) finds you well' politely establishes a friendly connection between you and the recipient of your letter and in most circumstances is a great way to start it. Especially if you're asking for something, it's good to indicate your concern for the person you're writing to. For the same reason, it's a good idea to end the letter with a phrase or sentence that will similarly show interest in their work or their well-being. 'Best regards,' is fine, but if you can tailor it in a way that's a bit more thoughtful, it's better. 'I hope your book/project continues to go smoothly.' (This can be followed by a 'Best regards.') If this is a person you don't know, you may have to settle for a generic 'Best regards' alone.
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Q: Which is correct? The thief carried the knife carefully so as not to cut himself. The thief carried the knife carefully not to cut himself.

A: The first one. The second one sounds quite awkward, and in fact one way I can think of to improve it would be to add a comma: 'The thief carried the knife carefully, not to cut himself'. The slight pause is meant to suggest the missing 'so as'!
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Q: There is a person in my current daily life who never admits his wrongs. He is always quick to blame others first and always believes that he is not wrong. Even when he is proven wrong, he still believes he shouldn't be sorry and isn't wrong. Is there a single-word adjective to describe this behavior? If not, a better way to describe this person would also make do. While stubborn and irresponsible fit, I feel like they don't tell the whole story. By this, I mean if I were to say to others that he is very stubborn and irresponsible, it is not implicitly implied that he blames others and never acknowledges his own fault. Edit: I believe my question is different because the person will also never acknowledge their wrongdoing. On top of blaming others, even after it has been proven to be their fault, they will not admit wrong doing. So aside from blaming others, they refuse to acknowledge the possibility that they have committed a mistake.

A:
Sounds like a remorseless/unrepentant person. ODO: remorseless ADJECTIVE 1 Without regret or guilt. 'We're given to understand that because Charlie is tormented by guilt that he somehow occupies a higher rung on the moral ladder than his unrepentant, remorseless elder brother.' unrepentant ADJECTIVE Showing no regret for one's wrongdoings. 'he was unrepentant and said that his comments were completely accurate'
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