This is a good example to understand the transcription:
The tools of DNA replication are:
the DNA itself, which is assimilated to the original paper to be photocopied.
The DNA polymerase, which is assimilated to the photocopier (it is she who will replicate the DNA).
The nucleotides: which are assimilated to virgin paper and ink (once assembled (photocopied with respect to the original DNA), they will give the DNA copy).
The electric current is assimilated to ATP, in fact ATP plays a very important role in the operation of the enzyme (the photocopier).