BESIDE VS BESIDES

Beside’ is a preposition and means ‘At the side of’ or ‘By’.

Who is slim girl sitting beside Hob?

 

Besides’ is either a preposition or an adverb.

As a preposition, it is used rather like ‘As well as’, whenever we have to add new info to what is already known.

Besides math, we have to study chemistry and physics. – We have to study chemistry and physics as well as math.

Who was on the trip besides John and Mary? – I knew about John and Mary, but who else was on the trip?

 

As an adverb, it means ‘Also’, ‘Moreover’, or ‘As well’ and usually goes before a clause.

I don’t like her lifestyle; besides, she is too superior.

It is too late to dine out. Besides, the restaurant is being crowded.