Ser v. Estar; Why Use Ser Here?
I almost completely understand when to use Ser and when to use Estar, but I recently got a question that contradicted my previous thoughts. The sentence read, in English, "The party is in a restaurant.." I immediately wrote, "La fiesta está en un restaurante..." However, I now see that the correct answer is, "La fiesta es en un restaurante..." Is this because the party is temporary? Why is 'ser' used here?
Any information is much appreciated!
5 Answers
Events such as a party always use ser. This has nothing to do with temporary.
Here's a link to my article on "ser" and "estar" It covers events like the party at the restaurant.
Instead of ser = permanent & estar = temporal, (which is a rule of thumb for beginners and gets you in trouble with exceptions such as: "Ella es virgen." (let's hope that's not permanent!) & "Él está muerto." (let's hope that is!) at your level you should apply the much more universal guideline:
ser = inherent & estar = state of being.
For example, a characteristic typical of coffee is that it's a hot drink, so you'd define it as: "El café es caliente.", but if you'd want to stress that your cup of coffee is in an especially hot state, you'd say: "El café está caliente." The same goes for people: if you tell a woman that "Eres bonita.", it implies you think she in inherently beautiful, (because of her face, body, her confident/happy ways etc.) whereas if you tell her "Estás bonita.", it sounds more like you think she is currently in a(n especially) beautiful state (because she is smiling, because of her clothes, make-up etc.).
There are whole lists of reasons for when to use ser, such as definitions and locations of origin, just like for estar, which include current location and emotional state, but they basically all boil down to whether what you want to say about the subject is inherent to it or not.
In your example,
natives of Spanish see the location of an event inherent to its being: without a place, just like without a date, an event does not exist, it isn't placed somewhere, it takes place somewhere; that's why you use ser. Natives of Spanish feel differently about buildings and people being at a certain place. For people, I hope this will be obvious now, as your current location isn't inherent to your being. When talking about buildings however, it isn't as straightforward for foreigners, but that's the fun in learning a language: you get to know a whole different perspective on the world. 
Just remember that to refer to the location of any event: weddings, exams, meetings, festivals etc. you use 'ser'. I hope this helps!!
If you think about it, the is that is used in English to mean a state of being, let's say temporary, eg, ‘este café está frío!’ or ‘this coffee is cold’ —has got nothing to do with the one where it is used to indicate the happening of something, eg, ‘the party is [happening] in a restaurant’. Really, the BE verb is reused here for both meanings, and another language is quite allowed to use two different words to signify them.
Your diagnosis (which will be sound in a state-of-affairs scenario) fails here because the case happens to belong to the second type where the ser would be the word to use.
Hello tfordham,
Welcome to the Spanishdict forum
You said/asked:
I almost completely understand when to use Ser and when to use Estar, but I recently got a question that contradicted my previous thoughts. The sentence read, in English, "The party is in a restaurant.." I immediately wrote, "La fiesta está en un restaurante..." However, I now see that the correct answer is, "La fiesta es en un restaurante..." Is this because the party is temporary? Why is 'ser' used here? Any information is much appreciated!
The SpanishDict grammar section states:
Exception: For the location of an event or party, use Ser: La fiesta es en mi casa. (The party is at my house.) Su boda es en una viña. (Their wedding is at a vineyard.)
In most cases, the verb estar is used to indicate the location:
eg: Estamos en la plaza = We are in the square
As Julian correctly stated, the verb's status: being temporary or permanent has nothing to do with the use of Ser here! (it is irrelevant)
The temporary vs permanent argument that many beginners like to quote can be very confusing and misleading because there are many exceptions, so it it is better to forget that and learn how the natives use these and other verbs. There are other guidelines which are much more useful and accurate! For example, the verb ser is used to describe a person's characterisstics eg: (él) Es amable = He is kind or the verb estar is used to indicate a person's position eg: She is standing = (Ella) Está de pie
You can read more about the use of verbs in the Spanishdict grammar section. Here is a useful direct link: enter link description here
I hope this helps
