1. How many rowers are there on a team?

2. How many rowers are there in a team?

3. I'm actually on the school badminton team.
4. I'm actually in the school badminton team.

(Which preposition do we have to use?)

5. Everyone is doing very well.
6. Everyone is going greatly.
7. Everyone is doing great.

(Which ones are grammatical?)

"on" is usually used when referring to being on a team.

#5 is the grammatically correct sentence, even though #7 is used in casual speech. #6 is not used.

Thank you for your help. There was an error in the previous sentence. What about #6 below?

5. Everyone is doing very well.
6. Everyone is doing greatly.
7. Everyone is doing great.

#6 is not used in normal English speech. The word "greatly" is an adverb, but is not normally used in this way. Here is a sentence that shows how to use "greatly" --

Her help was greatly appreciated.

It's best used as an adverb modifying an adjective, not modifying a verb. I know it's odd, but ... that's English!

1. To find out how many rowers are on a team, you would need to gather information specific to the team in question. The number of rowers on a team can vary depending on factors such as the type of rowing (e.g., single scull, double scull, quad scull, eight), the level of competition (e.g., high school, college, professional), and the specific team or event. It would be best to consult the team's official website, coach, or relevant documentation to determine the exact number of rowers on the team.

2. Similarly, to determine the number of rowers in a team, you would follow the same process mentioned above. The specific terminology used in different regions or contexts may vary, but the objective is the same.

3. Both "on" and "in" can be used to describe membership in a team, including the school badminton team. However, the choice of preposition can depend on the context or preference of the speaker/writer. In this case, both "on" and "in" would be acceptable, and it would be a matter of personal choice.

4. Similarly, both "on" and "in" can be used when referring to being a part of the school badminton team. Both prepositions are commonly used to describe membership or participation in a team, so the choice between "on" and "in" again comes down to personal preference or regional variations.

5. "Everyone is doing very well" is grammatically correct. The adjective "very well" is used to describe the manner or quality of how everyone is doing, indicating positive performance or progress.

6. "Everyone is going greatly" is not grammatically correct. The verb "going" is not typically used to describe how someone is performing in a general sense. "Going" is more commonly used to describe physical movement or transportation.

7. "Everyone is doing great" is grammatically correct. The adjective "great" is used to describe the manner or quality of how everyone is doing, indicating positive performance or progress. This is a commonly used phrase to express overall satisfaction or approval of everyone's performance.