A number of prepositions have affinities with other word classes. In particular, some prepositions are verbal in form:
Following his resignation, the minister moved to the country
I am writing to you regarding your overdraft
The whole team was there, including John
We refer to these as MARGINAL PREPOSITIONS. Other marginal prepositions include:
concerning, considering, excluding, given, granted, pending
Non-verbal marginal prepositions include worth (it's worth ten pounds) and minus (ten minus two is eight).