Hello Eunhye!

Thank you for your questions and here are my answers!
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1. Article in front of a proper noun.

In your sentence, I can see "a Mc donalds and dunkin donuts"
Should we use 'a' in front of proper nouns like brand name ?
If so, why 'a' Mc donalds and just Dunkin Donuts? (not 'a' dunkin donuts)

I'd like to know basic rules of using articles with proper nouns


-> Frankly speaking, I don’t think there is a good way to explain this to you. I am sure the basic ideas of using “a” over “an”, or using “a/an” vs “the, could be understood using many learning resources online. To start, I would simply search up “How to use an article/관사 사용법” on YouTube. You will find A LOT of resources that actually teach you some useful stuff.

Now, even when you learn what all of those YouTube videos teach you, you will still be confused. That’s simply because of irregularities. Even English speaking people will often not know why they use “the” in front of something rather than “a/an” and vice versa. It just happens - at least for most of them.

So how do you go on about this problem? I know this may not sound very helpful but read a lot. Listen a lot. Try not to think of it as learning but acquiring.

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2. In convenience, airplanes can not compare to helicopers

1) I'm rather familiar with the passive form of the verb 'compare' like in "Something is compared to something"
In your sentence, 'compare' is in active form. what's the difference?

-> There is no difference but the grammar part. If you were to say compared, you would say “airplanes cannot be compared to helicopters …”

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2) I can see nouns in plural forms like helicopters, airplanes.
Is it to refer to general airplane ? Can I say 'a airplane' instead of 'airplanes' here?

-> Perhaps “an airplane” and although it would make sense, when we are being general talking about the entire ‘kind’ of things, I think it is more common to leave them in a plural form.

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3. Emergency service
Does this word imply "medical" service?
I translate 긴급의료서비스 into "emergency medical service"

-> I believe in many cases it does imply the medical part. I believe either is a fine answer.


4. Helicopters are used for traffic control, rescue operations, espionage, emergency service and a quick means of travel.

1) Why don't we use articles (a, an, the) in front of the nouns here?

-> I will refer you to my first answer!

2) I think 'helicopter itself is means' , so the sentence should be
Helicopters are used for traffic control, rescue operations, espionage, emergency service and (used) as a quick means of travel.


-> I understand what you are saying but I am not sure if it is even necessary to make the changes you mentioned. Saying “Helicopters are a quick means of travel” would sound fine to me in my opinion!


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I hope this is clear!

Best regards,

Mason U, CMI-Korean
Business Interpretation and Translation in Korean (BIT-K) Instructor