Questions about example sentences with, and the definition and usage of "Yen"

A: In the forex market the US dollar vs the Japanese yen is USD/JPY.

It means the value of the yen has gone down

A: I have 4950 (= 5000 - 50) yen.

A: Actually, to charge is usually to take away money from something or someone, although it might sometimes mean to give money, too I suppose. I don't know what an IC card is, though.

A: I think it depends on context, but most likely it means 500Y won't be enough for lunch. Lunch will cost more than 500Y.

A: This costs 900 yen
Hope it helps!

A: This shirt costs 500 yen, May I borrow 500 yen?, I lost 500 yen, I can give you 500 yen, I will buy it for 500 yen, I don't have 500 yen, I need 500 yen. I hope this helps!

A: technically they’re both uncertain since “I guess” is used when you think you may be right but you’re not sure. Sorry if I confused you I was mostly talking about that😅

A: "Some" is used less often when talking about sums of money, although it isn't unheard of. It is slightly "looser" and more casual in tone, you might hear someone use it when telling a funny story. "About" is more common today and is more neutral sounding

A: It requires context, but they can be both used in some circumstances and at times would be.

But the first one is explicit, it is addressing the two people, either the two in front of them, or on the phone when you have named yourself and another for an appointment, they are saying.. this is the price for you and this person.

The second way is far more general. It is telling you this is the price for the person they are talking to and another person.

But as mentioned they are used interchangeably

A: How many is used when there is an amount that can be counted.
How much is used when the amount can't be counted.

Basically, it matters whether you are using a unit of measurement.

Examples:
"How much water is in the bucket."
"How many liters of water do we have?"

So, for Yen, you should use "How many."

A: You can get something for doing something or you can get something by doing something. I think by is used more when you make it yourself, like I made the sauce by mixing something and something. For is more for if you get something for doing something, like in you're example sentence, or in a sentence like: I got candy for helping out my mom. So in you're example, you'd use the first one, with for.

A: I hear 1 more often.

A: Both are correct. Some people prefer 2 because they only use "over" when talking about one thing being physically above another thing.

A: thirty thousand yen

~three hundred dollars.

A: There's no need to apologise. It's not easy for us to understand each other.

I was concerned that your example might not be "rounding" but now I'm sure it is.

So, I would say:

"Round the amount to the nearest 1000 yen. Odd amounts up to 499 yen will be rounded down, and odd amounts over 500 yen rounded up."

A: I loaned him 500 yen. Or I lent him 500 yen. You can use both.

Another usage:

He took out a loan (from the bank) to pay for the car.

A: both of those sentences sound very natural! I think I would say the first sentence more often, but both are good!

A: Betting is a part of gambling. If someone wants to bet you ¥1000 on something, if they are right or they win, you have to pay them ¥1000. If they lose, they have to pay you ¥1000.
Example one: You and your friend are watching a sports team play a game. You bet ¥1000 that team A will win. Your friend bets that team B will win. If team A wins, your friend has to pay you ¥1000.

Example 2: Your friend says, “I bet you ¥1000 that I can eat 10 hotdogs in one minute.” If he can’t do it in one minute, he has to pay you ¥1000. If he does it, you have to pay him.

A: I think it’s better to say *A* 100,000 yen credit card pre-authorization. Otherwise, it’s perfect!

A: Japan's currency is the yen.