Copyrighted music

For our film we have been told that we are not allowed to use anyone elses music if it is copyrighted and this is what it means:

'Copyright protects creative works and enables composers, literary authors and other creators to be paid for their work. Copyright is the means by which those who create and own works (e.g. music and lyrics) can control who makes use of each work and the circumstances in which it is used, to ensure that the integrity and value of the work is respected.'

'Copyright in a song
Every song comprises two copyright works:

The music itself (a musical work)
The lyrics/words (a literary work)'

'Rights of the owner
Subject to certain limited exceptions set out in the CDPA, if you own the copyright in either type of work, you have the sole right do any of the following, or to authorise another to do so:

Copy the work
Issue, lend or rent copies of the work to the public
Perform, show or play the work in public
Communicate the work to the public (i.e. broadcast it via television, radio, online etc.)
Adapt the work'