Q: That is bought. とはどういう意味ですか?
A: It means some things is bought but you don't know how bought it, it is an important crammer that we call it "passive form of verb" and Active form .
Active form has a subject like: I read the book that Jon had been writing about nature ( John is subject and we know who write the book) but in these sentence :
I read a book that was written about nature ( here we don't know how write it )
Passive form for simple present is some thing you write : is/are + past participle (for simple present)
Q: "You are not above undermining me." とはどういう意味ですか?
A: Yes!
"You are the kind of person who would undermine me"

"the kind" because you are referring to a specific kind, so you have to use the definite particle "the"

"person" because "you" refers only to one person

"would undermine" because English has a future tense that we need to use

Q: I was just not down to do that とはどういう意味ですか?
A: It means 'I was not willing to do that' or 'I didn't want to do that'.
Q: It is nice to finally meet you?
A: This is a polite statement after you have met someone that you have been wanting to meet. You would say this to the person you have met.
Q: To be just and convenient とはどういう意味ですか?
A: The injunction must be fair (just) and not too difficult (not too inconvenient).


Q: be afoot を使った例文を教えて下さい。
A: Something is happening that isn’t quite clear. Something is afoot.
Q: "it could be that" を使った例文を教えて下さい。
A: It could be that she is not feeling well today.

It could be that the world is experiencing climate change.

It could be that he is inexperienced.

It could be that winter is coming late again this year.

Yes. The phrase “it could be that” means “maybe” , but it is most used when answering someone else.
Q: been を使った例文を教えて下さい。
A: I've been there
Q: been を使った例文を教えて下さい。
A: I have been reading magazines.
Have you been enjoying your vacation?
How long has it been since you played an instrument?
Q: Where are you doing を使った例文を教えて下さい。
A: what are you doing there?


Q: I was surprised to hear that. と I was taken aback to hear that. はどう違いますか?
A: if you are “taken aback” that mean that something is really surprising
Q: it is located .... と it is situated... と it is sited... はどう違いますか?
A: Situated mean it's a brief clue of where something is roughly located.
"It is situated in (or near) Cardiff."
The location is the direct position or area of where something is situated.
"My location is blah..... And my job is situated towards the east."
Q: I am sorry to keep you waiting so long.
と I am sorry I kept you waiting so long. はどう違いますか?
A: "Keep" is present tense and "kept" is past tense, so if the person is still waiting you would say the first one. If they are not waiting anymore, you would say the second one. If you are talking to a person while doing something they are waiting on, you can say, "I am sorry to keep you waiting so long," but if you have already finished what the person is waiting on you can say, "I am sorry I kept you waiting so long."
Q: He is going to resign. と He is to resign. はどう違いますか?
A: he is to resign doesn't make sense. if you want to say that in present tense you would say "he resign"
Q: What will you be having? と What will you have? はどう違いますか?
A: They technically mean the same thing. For example, if you were in a fast food restaurant and you are the passenger, the driver might ask you “what will u have?” But “What will you be having” is a more formal way of asking.


Q: What is this? は 英語 (アメリカ) で何と言いますか?
A: "hanging loop"
Q: Why is it wrong “I saw you walking with your dog”? は 英語 (アメリカ) で何と言いますか?
A: I saw you walking your dog. "Walk the dog" is a phrase and doesn't need "with".
Q: what is sushi? は 英語 (アメリカ) で何と言いますか?
A: QAの全文をご確認ください
Q: What is this は 英語 (アメリカ) で何と言いますか?
Q: is it okay to be here は 英語 (アメリカ) で何と言いますか?
A: I explained the first couple of questions with the answers but if you have any questions about the answers I gave I can explain them as well! :)


Q: Why are you so well-dressed? Where are you going? この表現は自然ですか?
A: Yes, these are natural sentences. For the first sentence we would very commonly also say why are you so dressed up?
Q: what are you going to do later? この表現は自然ですか?
A: What are you going to do later?

Don't forget to start every sentence with a capital letter.
Q: "I've never been interested in where it originates from." この表現は自然ですか?
A: natural:)

or... where it originated from...

either way, I think.
Q: "What am I wrong? It's just what it's supposed to be." この表現は自然ですか?
A: Oh I see. You are trying to say “내가 뭘 잘못했어??? 먹으라고 만든 것인데!” Right?

If so I would say, “What was wrong with eating all that bread? That’s what it’s for!” Or more casually, “I’m not sorry! Bread is for eating.”
Q: I was surprised that he retired. I hoped he kept performing more. この表現は自然ですか?
A: × I hoped he kept performing more.
✓ I hoped that he would keep performing more. Or
I hoped that he had kept performing.