My teachers says that "debe" means must.
My question is that does "debe" always mean "should", I thought it only meant "must" and that "debería" meant "should." Is what my teacher said correct or should she have used "debería"?
My teachers says that "debe" means must.
My question is that does "debe" always mean "should", I thought it only meant "must" and that "debería" meant "should." Is what my teacher said correct or should she have used "debería"?
I think your confusion comes from two different forms of deber: deber and deber de, which are NOT the same. I see very surprising how nobody has highlighted this.
The conditional (debería) is used for advice and it is equivalent to "should".
For example: "I should go" is (yo) debería ir
This is easy to remember, so let's go to the key part.
"Deber" (non conditional) is used for compulsory duties, and it is equivalent to "must".
For example: "I must go" is (yo) debo ir.
However, there is a "phrase" that changes its meaning. When it is "deber de", it means "possibility" instead of duty.
"Deber de" indicates possibility/probability. It is different than just "deber".
It is probably the in the podium of the most commited mistakes in oral speech (sharing positions with "leísmo", "laísmo", or the imperative of "vosotros", haha).
When you say "deber de", it denotes possibility.
Example: Debe de haber 10 personas means "It must be 10 people", in the sense that "It is probable that there are about 10 people.
Check the difference:
"Debe ser grande" = It MUST be big
vs.
"Debe de ser grande" = It is probably big.
It can be sometimes hard to decide, but most examples are clear enough.
So, since this is a very common mistake, I just wanted to highlight it and point it out. If this wasn't yoru confusion, tell us.
My teacher says that "debe" means must.
My question is, does "debe" also mean "should"? I thought it only meant "must" and that "debería" meant "should." Is what my teacher said correct or should she have used "debería"?
Indeed, "debe" also means "should." You can see in WordReference.com that deber means:
have to, must, oblige [somebody] to, should
What your teacher wrote was fine. Her explanation of the verb "deber" was perhaps an oversimplification. I will encourage you to find a dictionary you like and make it your friend.
Note, there is often not a perfect one-to-one match between words of different languages. "Should" can be translated as both "debe" and "debería", depending on the context.
Here is a simplified way of thinking about the choice of debe/debería: debería often has more of an "ought to" feel than debe.