In both cases, "my" infers you are specifically concerned with your own performance.
2. English speakers may not be plentiful in the country I am going to visit.
4. Soccer is not as popular in the United States.
- Why don't you practice speaking more?
2. I'm worried about English.
- ( )
(Is this correct without 'my' before 'English? What is the difference between #1 and #2? What will be the answer to the question 2?)
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3. I'm worried about my soccer.
- Why don't you practice kicking balls more?
4. I'm worried about soccer.
- ( )
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What is the difference between #3 and #4? Is there any difference between them? What will be the answer to the Question 4?
2. English speakers may not be plentiful in the country I am going to visit.
4. Soccer is not as popular in the United States.
3. Similarly to #1, the difference between #3 and #4 is that in #3, the speaker is specifically worried about their own soccer skills, while in #4, the concern is about soccer in general. The answer to Question 4 would be similar to the answer for #3, suggesting that the person should practice kicking balls more to improve their soccer skills.