Sports center vs Sport center?

[Schwartz]

1. Why we use 'sports center' instead of 'sport center'.

2. People complain that the costs of campaigning are so high.
Why we use 'costs' and 'are' instead of 'cost and 'is'.

3. From above questions. Is 'Why we use .....' correct?, or the correct one is 'Why do we use....'.

[Milanya]

1. sports center [countable]
- a building where people can go to play many different types of indoor sports
http://www.ldoceonline.com/dictionary/sports-centre

2. I think that there are many different costs involved in a campaigning.

3. 'Why do we use....'. is correct.
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con·text - The part of a text or statement that surrounds a particular word or passage and determines its meaning.

[Kitosdad]

Are is usually used for plural text, and is for singular.

"There is a car parked outside."

"There are a number of cars parked outside."
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[Prezbucky]

Cue the Michael-Bay-production battle music...

Narrator:

Americans refer to them as sports. Brits refer to it as sport. Which rendering do you prefer?


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