To go about the initial step in doing (something)
To come into being
To begin to appear or develop
It is best to commence the electrolytic thickening in a silver acetate bath.
The bombardment will commence on September.
We may conveniently commence with them on account of their simplicity and great importance in respect to the theory of optical instruments.
But when the combat was about to commence it was interrupted by the king...
Aphides are born, as a rule, alive, and the young soon commence to reproduce again.