Grammar exercise focusing on proper comma usage in sentences.

Exercise 1: Comma Usage in Sentences

#### Explanation of Commas:
Commas are used to separate elements in a sentence for clarity and readability. They help to indicate pauses, separate items in a list, set off introductory phrases, and clarify the structure of complex sentences. Below is the analysis of each sentence with justification for comma placement.

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#### Sentences with Commas Added:

1. When going on a trip, I like to take my guitar with me.
- Justification: A comma is needed after the introductory phrase "When going on a trip" to separate it from the main clause.

2. I’ve been to France, Germany, China, and Spain.
- Justification: Commas are used to separate items in a list (France, Germany, China) before the conjunction "and."

3. Next week I am going to have a party, so I invited my friends Mark and Sue.
- Justification: A comma is needed before the conjunction "so" to separate two independent clauses.

4. There are exactly 4897341 people living in this city, most of whom take a train, a bus, or a tram to work.
- Justification:
- A comma is needed after "this city" to separate the main clause from the non-restrictive relative clause "most of whom take a train, a bus, or a tram to work."
- Commas are also needed to separate items in the list "train, a bus, or a tram."

5. “Look at this,” he whispered.
- Justification: A comma is needed after the quoted speech ("Look at this") to separate it from the dialogue tag "he whispered."

6. Paulina’s wife, of many years, decided to live in Greece.
- Justification: Commas are used to set off the non-essential phrase "of many years," which provides additional information about Paulina's wife but is not essential to the meaning of the sentence.

7. As the plane was coming to a halt on the runway, I was beginning to feel less nervous.
- Justification: A comma is needed after the introductory phrase "As the plane was coming to a halt on the runway" to separate it from the main clause.

8. The thief had very impractical shoes, so he couldn’t run very fast.
- Justification: A comma is needed before the conjunction "so" to separate two independent clauses.

9. “I’m warning you,” said the teacher, “don’t even try to cheat or else you will be expelled from school.”
- Justification:
- Commas are needed around the dialogue tag "said the teacher" to separate it from the quoted speech.
- The comma after "you" separates the first part of the quote from the second part.

10. I dedicate this work to my brothers John Smith and God.
- No commas needed. This sentence does not require any commas because it is a simple declarative sentence without any lists or non-essential clauses.

11. Sarah, the most intelligent pupil in the class, was always late for school.
- Justification: Commas are used to set off the non-essential phrase "the most intelligent pupil in the class," which provides additional information about Sarah but is not essential to the meaning of the sentence.

12. I said that she is intelligent, not pretty.
- Justification: A comma is needed to separate the two contrasting ideas "intelligent" and "not pretty."

13. Once the storm was over, we could sail to the island.
- Justification: A comma is needed after the introductory phrase "Once the storm was over" to separate it from the main clause.

14. Given the terrible weather conditions, it is surprising that the holiday was so enjoyable.
- Justification: A comma is needed after the introductory phrase "Given the terrible weather conditions" to separate it from the main clause.

15. India, a truly beautiful, interesting, and exotic country, is now a popular tourist destination.
- Justification:
- Commas are used to set off the non-essential phrase "a truly beautiful, interesting, and exotic country."
- Commas are also used to separate items in the list "beautiful, interesting, and exotic."

16. During lunch at the campus cafeteria, Henry noticed the dirty tables, the overworked cashiers, and the high prices of food.
- Justification:
- A comma is needed after the introductory phrase "During lunch at the campus cafeteria" to separate it from the main clause.
- Commas are used to separate items in the list "dirty tables, the overworked cashiers, and the high prices of food."

17. During the race I tried to keep up with Mark who can run 100 meters in under 12 seconds.
- No commas needed. This sentence does not require any commas because the relative clause "who can run 100 meters in under 12 seconds" is restrictive and essential to the meaning of the sentence.

18. To study for the exam Bill drank seven cups of coffee which kept him awake all night.
- No commas needed. This sentence does not require any commas because the relative clause "which kept him awake all night" is restrictive and essential to the meaning of the sentence.

19. I only earn 2000 USD a month for my hard work, and my wife gets 12000 USD which is not fair.
- Justification: A comma is needed before the conjunction "and" to separate two independent clauses.

20. Ron who is 15 was doing his best to win the contest but he failed.
- No commas needed. This sentence does not require any commas because the relative clause "who is 15" is restrictive and essential to the meaning of the sentence.

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Exercise 2: Comma Usage in Text

#### Explanation of Commas:
The text provided is a narrative paragraph. Commas are used to separate clauses, set off non-essential phrases, and clarify the flow of the story. Below is the analysis of the text with justification for comma placement.

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#### Text with Commas Added:

Last week, I decided to visit my best friend John. He is a very smart, handsome, and kind person, and he always manages to find some time for me. Last week, however, the situation was different. Because he had just got a new job, John had very little free time. Nevertheless, we managed to arrange a quick 15-minute-long meeting in the “Blue Rose” café, which is said to be owned by a very famous actor. I was wearing my checked red green and blue T-shirt, my brown trousers, and a pair of sneakers. I arrived at 9:30, and John at 9:45. The waiter who was working that day took our order. We weren’t hungry, so we only ordered drinks. John, who seemed rather tired, told me that his new job was very time-consuming, demanding, and difficult. “I don’t know if I’ll manage to work like that for long,” John said. However, he also admitted that his job had advantages, some of which were: a comfortable working environment, free lunch for each employee, and a salary of over 11000 USD. “That’s a lot of money!” I said. “Do you even know?” I asked, “what to spend it on?” John had no ideas, but if I had that much money, I would probably go on a long holiday, renovate my house, and buy a new car. That car would have to be fast, comfortable, and safe. Our conversation ended quickly because John had to go back to work, and I had a bus back home to catch. When I reached for my wallet to pay for my drink, John offered to pay for everything, which was very nice of him. “That’s something I can spend my money on,” he said. “I can pay for my friends’ drinks, lunches, and so on.”

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#### Justification for Commas:

1. "Last week, I decided to visit my best friend John."
- Justification: A comma is needed after "Last week" to separate the introductory phrase from the main clause.

2. "He is a very smart, handsome, and kind person, and he always manages to find some time for me."
- Justification:
- Commas are used to separate items in the list "smart, handsome, and kind."
- A comma is needed before the conjunction "and" to separate two independent clauses.

3. "Last week, however, the situation was different."
- Justification: Commas are used to set off the transitional word "however" for clarity.

4. "Because he had just got a new job, John had very little free time."
- Justification: A comma is needed after the introductory phrase "Because he had just got a new job" to separate it from the main clause.

5. "Nevertheless, we managed to arrange a quick 15-minute-long meeting in the ‘Blue Rose’ café, which is said to be owned by a very famous actor."
- Justification:
- A comma is needed after "Nevertheless" to separate the introductory word from the main clause.
- A comma is needed after "café" to set off the non-essential phrase "which is said to be owned by a very famous actor."

6. "I was wearing my checked red green and blue T-shirt, my brown trousers, and a pair of sneakers."
- Justification: Commas are used to separate items in the list "checked red green and blue T-shirt, my brown trousers, and a pair of sneakers."

7. "I arrived at 9:30, and John at 9:45."
- Justification: A comma is needed before the conjunction "and" to separate two independent clauses.

8. "John, who seemed rather tired, told me that his new job was very time-consuming, demanding, and difficult."
- Justification:
- Commas are used to set off the non-essential phrase "who seemed rather tired."
- Commas are used to separate items in the list "time-consuming, demanding, and difficult."

9. "‘I don’t know if I’ll manage to work like that for long,’ John said."
- Justification: Commas are used to separate the quoted speech from the dialogue tag.

10. "However, he also admitted that his job had advantages, some of which were: a comfortable working environment, free lunch for each employee, and a salary of over 11000 USD."
- Justification:
- A comma is needed after "However" to separate the introductory word from the main clause.
- Commas are used to separate items in the list "a comfortable working environment, free lunch for each employee, and a salary of over 11000 USD."

11. "‘That’s a lot of money!’ I said. ‘Do you even know?’ I asked, ‘what to spend it on?’"
- Justification: Commas are used to separate quoted speech from dialogue tags and to clarify the structure of the questions.

12. "John had no ideas, but if I had that much money, I would probably go on a long holiday, renovate my house, and buy a new car."
- Justification:
- A comma is needed before the conjunction "but" to separate two independent clauses.
- Commas are used to separate items in the list "go on a long holiday, renovate my house, and buy a new car."

13. "Our conversation ended quickly because John had to go back to work, and I had a bus back home to catch."
- Justification: A comma is needed before the conjunction "and" to separate two independent clauses.

14. "When I reached for my wallet to pay for my drink, John offered to pay for everything, which was very nice of him."
- Justification:
- A comma is needed after the introductory phrase "When I reached for my wallet to pay for my drink" to separate it from the main clause.
- A comma is needed after "everything" to set off the non-essential phrase "which was very nice of him."

15. "‘That’s something I can spend my money on,’ he said. ‘I can pay for my friends’ drinks, lunches, and so on.’"
- Justification: Commas are used to separate quoted speech from dialogue tags and to clarify the structure of the sentences.

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Final Answer:

The solutions for both exercises are provided above with detailed justifications for each comma placement.

Final Answer:
\boxed{\text{See explanations above for comma placements and justifications.}}