The government ___ decided ...: HAVE or HAS?

Today I got asked a question that has been asked again and again: Should we use plural or singular verb with words like "the government"?

Below is the answer taken from ESL Forums. I think their answer is totally adequate, so I don't have to add anything here.

Enjoy!
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The government have (or has?) decided to do something about pollution.

In English, we often use singular nouns that refer to groups of people (eg government, committee, team) as if they were plural. This is less true in US English.

This is because we often think of the group as people, doing things that people do (eating, wanting, feeling etc).

In such cases, we use:

- plural verb
- plural pronoun (they)
- who (not which)

Here are some examples:

- The committee want sandwiches for lunch. They aren't very hungry.
- My family, who don't see me often, have asked me home.
- The team hope to win next time.

Here are some examples of words and expressions that can be considered singular or plural:

choir, class, club, committee, company, family, government, jury, school, staff, team, union

the BBC, board of directors, the Conservative Party, Manchester United, the Ministry of Health

But when we consider the group as an impersonal unit, we use singular verbs and pronouns:

- The new company is the result of a merger.
- The average family consists of four people.
- The committee, which was formed in 1983, has ceased to exist.

Nguồn: http://www.englishclub.com/esl-forums/viewtopic.php?t=27288