Expertlatin
When can you use per?
You use per to talk about each one of something. For example, if a vehicle is travelling at 40 miles per hour, it travels 40 miles each hour. Buses use much less fuel per person than cars.
What is the adjective of Per?
per- a prefix meaning “through,” “thoroughly,” “utterly,” “very”: pervert; pervade; perfect. Chemistry.
Is it OK to use as per?
The choice of which to use (or avoid) is entirely a matter of taste. The more ponderous as per is often found in business and legal prose, or in writing that attempts to adopt a formal tone. It is not incorrect to use, but some find it overly legalistic and counsel avoiding it for that reason.
Can you just say as per?
Per can mean according to or in accordance with — so it's not wrong, exactly. People often use it to make their writing more formal, but it sounds fusty. Writing guides usually condemn it as jargon. As per is worse — it's not only fusty but also redundant, which makes it silly.
