I don't understand the difference between these sentences. Is there a special usage for each?
I used to have three cats
and
I had three cats
I don't understand the difference between these sentences. Is there a special usage for each?
I used to have three cats
and
I had three cats
The phrase used to (do something) suggests a continuity of practice (from 'use'), a habit, a matter of course, a regular feature, or something customary in nature compared to have (something) that has a static/ momentary implication.
I used to have three cats
Having three cats was a natural, it was always so, for some time, was nothing unusual at that time, I was accustomed to having three cats, …
I had three cats
That's it. I had them. At a point of time. I am not saying anything more about it. May be it was for a day, may be for an hour, or for a year.
See TFD idioms:
A young lady who used to work in my office had seven brothers!
We used to visit our parents at Christmas every year.
Compare: used to work (a routine) & had seven brothers above.
Notice: used to visit in reference to at Christmas every year. (customary)
I would use 'I had three cats' if I'm within a context that defines the time frame I'm talking about. Without this, it remains incomplete. For example, you can be talking about when you were living somewhere or when you were a certain age, then 'I had three cats' is acceptable and unambiguous, doesn't beg the question 'when?'
'I used to have three cats' on the other hand can be used without defining this context beforehand and is still acceptable, it sets a context of a time in the past and that time is not necessarily significant to the telling of the story.