1. Best of all, I can sing Korean pop songs with my friends.

2. Most importantly, I can sing Korean pop song with my friends.

(Are both the same in meaning?)

3. I fougnt with Don badly.
4. I fought with Don teribly.
5. I fought with Donheavily.
6. I fought with Tom very much.

(Ae they all the same and grammatical?)

7. I was angry at Don.
8. i was angry with Don.
(Which preposition do we have to use?)

1. Best of all, I can sing Korean pop songs with my friends.

2. Most importantly, I can sing Korean pop song with my friends.

(Are both the same in meaning?)

3. I fougnt with Don badly.
4. I fought with Don terribly.
5. I fought with Don heavily.
6. I fought with Tom very much.

(Are they all the same and grammatical?)

7. I was angry at Don.
8. I was angry with Don.
(Which preposition do we have to use?)

Both 1 and 2 are the same and correct.

Put the modifiers of fought right after the verb. I fought badly - would mean that you were not a good fighter.

Did you mean that you had a bad ( terrible) fight? Then you need to say I had a terrible fight with Don.

Heavily would not be used.

"often" would be better than "very much".

7 and 8 are interchangeable.

1. "Best of all, I can sing Korean pop songs with my friends" and "Most importantly, I can sing Korean pop song with my friends" have slightly different meanings.

The phrase "best of all" suggests that singing Korean pop songs with friends is the most enjoyable or favorable aspect among other things you can do. On the other hand, "most importantly" suggests that singing Korean pop songs with friends holds the highest significance or importance among other activities you engage in.

2. Let's analyze each sentence individually:

- "I fought with Don badly." This sentence is grammatically incorrect. Instead, you can say "I had a bad fight with Don." It is more accurate and conveys the same meaning.

- "I fought with Don terribly." This sentence is grammatically correct. The word "terribly" is an adverb that describes the intensity or seriousness of the fight with Don.

- "I fought with Don heavily." This sentence is grammatically incorrect. Instead, you can say "I fought with Don a lot" or "I had a heavy fight with Don."

- "I fought with Tom very much." This sentence is grammatically incorrect. Instead, you can say "I fought a lot with Tom" or "I had many fights with Tom."

3. Both "I was angry at Don" and "I was angry with Don" are grammatically correct, but they convey slightly different meanings.

- "I was angry at Don" implies that your anger is directed towards Don. This indicates that he is the cause of your anger.

- "I was angry with Don" suggests that your anger is shared with Don, or that both you and Don are angry about something else. It implies a shared feeling of anger or frustration.

Depending on the context of the situation, either preposition can be used.