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.

[EX Q]: For example, a computer security expert can be an expert and making a basic mistake, perhaps unrelated to his personality but highly relevant to his field of expertise and a mistake that just about anybody could do but just because he is a security expert he especially should not have done it. I don't mean stupid mistake or stupid error but I mean contradictory and almost similar to a double-standard. Jeff teaches English but he couldn't spell 'occurrence'. Or for example George is a professional Microsoft Windows programmer but he doesn't know what alt+tab does. Or Henry is a surgeon but he cut himself shaving. I don't necessarily mean something like a police officer who himself is corrupt or a judge who is corrupt because those are not accidents or mistakes but deliberate. Albert Einstein was a genius but couldn't remember his own address and entered the wrong house when going home. (Perhaps the above Einstein example is not a great example because scientist could be absent-minded.) I mean more like actually mistakenly missing the basics of your own speciality or making a human error that anybody else could do except you because you are supposed to be the specialist. I think the classic example could be Bill Gates trying to show how good Microsoft Windows is and it crashes. Or a news anchor, who should be a specialist in not making a word mistake, actually makes a word mistake. Or a judge or an attorney, who should be experts in law and rights, wouldn't know something trivial about law and right e.g. unknowingly about that blackmailing is a crime. I almost made such a mistake myself. I was an IT specialist and computer technician at a client's office and their boss was teaching himself the basics of programming and asking me about something basic. I actually got it right but I was not completely certain about something basic while actually being able to solve complicated and advanced problems for them.
[EX A]: Such mistakes are bloopers. ODO: blooper NOUN North American informal 1 An embarrassing error 'Home cooks perhaps identified with Mrs. Child, who, though she clearly knew her sauces and souffles, also committed bloopers on camera.'

[EX Q]: Consider the following sentences: The last few years has seen the building of the new church. and The last few years have seen the building of the new church. As a native speaker, both of these sentences 'sound' correct to me. Is only one of them correct, are they both correct or is each one only correct in specific circumstances. This was a question one of my students asked me, so if there is a relevant grammar rule, that would be great.
[EX A]: Years, being plural, takes the plural form have. But the last few years, being a single span of time, takes the singular form, has. That's why they both sound okay to you. The first option is generally preferred in formal writing.

[EX Q]: I was laying in bed or lying in bed?.
[EX A]:
According to Google NGrams, 'lying in bed' is much more common. 'To lay' is a transitive verb. It can be reflexive - 'I lay myself', 'I am laying myself', 'I was laying myself' - but it requires an object noun. 'To lie' by contrast is intransitive. It is an indicator of state, not action. Thus, your statement, which indicates your state in the past perfect, should use this verb and not 'lay'. If 'I was laying in bed', the connotation is that I was in the act of laying something in that bed, and the sentence is not proper unless that object is either stated explicitly or inferred by context; it can range from the innocent reflexive ('I was laying myself in bed') to the innocent transitive ('I was laying my infant daughter in bed') to the sexual ('I was laying my girlfriend in bed') to the absurd ('I was laying eggs in bed').