Andy and Kate are really good singers. They can dance well,too.

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What does the first sentence above mean, #1 or #2?
1. They are prefessional singers and they sings well.
2. They are not professional singers. They just sing songs well.

The sentence says nothing about whether or not they are paid to sing in public. It merely states that they are good singers. Members of the church choir are often good singers, too, but are not professional singers. Maybe you're a good singer, but not a professional singer.