Since: conjunction, preposition, adverb
The word since can be a conjunction, a preposition, or an adverb.
Here are some examples:
‘Since’ as a preposition
- I haven’t seen him since this morning.
- Since joining the company, Mike has been promoted twice.
‘Since’ as a conjunction
Since is a conjunction when it joins two clauses:
- Mike has been promoted twice since he joined the company.
(clause 1 = ‘Mike has been promoted twice’; clause 2 = ‘he joined the company’) - We’ve made a lot of new friends since we came to live in Yorkshire.
- Let’s discuss the problem now, since you’re here.
More examples of since (conjunction)
‘Since’ as an adverb
- He left this morning and we haven’t seen him since.
- He was sent to prison, but has since been released.

Neeraj - April 27, 2017, 11:25 am
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Beros - November 15, 2019, 11:30 am
Wow….I have learned a lot… thanks.
Jason Ruiz - November 22, 2020, 2:08 am
What are the 9 parts of the speech of this sentence?
Since I could not postpone my message, I considered it urgent to write to you.