This is an interesting difference between British and American English.
Here's an advance warning. If you
a) want to make life easy for yourself
and/or
b) prefer to learn American English
you should leave this page now.
Go and read a good book. Enjoy the sunshine. Watch some football.
If not... read on. Unlike in AmE, where a singular collective noun ( such as group, team, family, government, police, council, committee) is always grammatically singular, in BrE these words can be either singular or plural. If you are considering the group as a single entity, you use a singular verb ( is, does, has); if you are talking about the individuals which make up this group, you use a plural verb (are, do, have).
For example:
1.Liverpool is leading 1-0
Here, "Liverpool" is treated as a singular noun. This is because you are comparing the success of one club with another.
2.Liverpool are attacking again.
Here, "Liverpool" is treated as a plural noun, because you are thinking about the individual players who are attacking.
Likewise, "The BBC is showing..." refers to the channel (singular), whereas "The BBC are planning..." refers to the people who are making these plans. "My family isn't poor" refers to the financial state of the family as a whole (singular), while "My family are normal" refers to the individual members of the family.
Still confused? Never mind.
For a start, these examples are fairly random - as a British English speaker, I'd be quite happy to have all of them in the plural (Liverpool are leading/My family aren't poor/The BBC are showing). Meanwhile, an AmE speaker - like your first answerer Craig Hall from the US - would change them all to singular verbs ('is' throughout).
And, finally, you - as a Chinese speaker - have more important things to worry about when it comes to noun/verb agreements than this one little anomaly.
Take my advice. Don't worry about it.