More information about prepositions. IN/ON/AT

Prepositions of Place: at, in, on

In general, we use:

• at for a POINT
• in for an ENCLOSED SPACE
• on for a SURFACE

at	in	on
POINT	ENCLOSED SPACE	SURFACE
at the corner	in the garden	on the wall
at the bus stop	in London	on the ceiling
at the door	in France	on the door
at the top of the page	in a box	on the cover
at the end of the road	in my pocket	on the floor
at the entrance	in my wallet	on the carpet
at the crossroads	in a building	on the left/right
at the front desk	in a car	on a page

Look at these examples:

• Jane is waiting for you at the bus stop.
• The shop is at the end of the street.
• My plane stopped at Dubai and Hanoi and arrived in Bangkok two hours late.
• When will you arrive at the office?
• Do you work in an office?
• I have a meeting in New York.
• Do you live in Japan?
• Jupiter is in the Solar System.
• The author's name is on the cover of the book.
• There are no prices on this menu.
• You are standing on my foot.
• There was a "no smoking" sign on the wall.
• I live on the 7th floor at 21 Oxford Street in London.

Notice the use of the prepositions of place at, in and on in these standard expressions:

at	in	on
at home	in a car	on a bus
at work	in a taxi	on a train
at school	in a helicopter	on a plane
at university	in a boat	on a ship
at college	in a lift (elevator)	on a bicycle, on a motorbike
at the top	in the newspaper	on a horse, on an elephant
at the bottom	in the sky	on the radio, on television
at the side	in a row	on the left, on the right
at reception	in Oxford Street	on the way

IN

a) Dentro de un espacio cerrado:

in the bedroom / in my office / in your pocket / in hospital / in prison / in bed

in the front / in the back of a car (pero; at the front / at the back of a cinema, of a building)

O dentro de un objeto:

in that book / in the water

b) En un lugar abierto (sitios determinados con unos límites definidos):

in the park / in the street / in the garden / in the queue

c) Con países y ciudades:

in Spain / in Madrid / in my country / in this town

ON

a) Sobre una superficie, con contacto físico:

on the table / on the wall / on the floor / on my shoulder / on page 103 / on the second floor

b) Con las expresiones:

on the left / on the right

AT

a) Lugar determinado:

at the door / at the window / at the trafic light / at the top of the page / at the bridge

b) Con las expresiones:

at home / at school / at work / at the office / at the bus stop / at the airport / at someone's house

c) Con acontecimientos:

at the party / at the meeting / at the conference

d) También se puede utiliza con edificios, con un significado diferente al de "in":

at the museum (en el museo: puede ser dentro o justo fuera)

in the museum (dentro del museo)

e) "At" se utiliza cuando se menciona donde tuvo lugar un acto:

This morning I visited the painting exposition at the National Museum

Yesterday we had dinner at the new Chinese restaurant

f) O con lugares abiertos con agua: "at": al lado; "in": dentro

at the river (en la orilla del río) / in the river (dentro del agua)

at the lake / in the lake

at the swimming pool / in the swimming pool

at the sea / in the sea

En numerosos casos con un mismo sustantivo se pueden utilizar diferentes preposiciones si bien el significado varía:

in the car (dentro del coche)

on the car (sobre el coche)

at the car (dentro o justo al lado el coche)

Watch out!!!

En muchos casos puedes usar "in" o "at" como "en" con la misma palabras pero en situaciones diferentes, por ejemplo:
Si dices "at hospital", es porque tienes una cita o visitas a alguien, pero si dices "in hospital", es porque estás internado por alguna dolencia o cirugía. Lo mismo sucede con "at school" (Escuela de día) e "in school" (Internado).
En general dices "he/she is AT his office", pero si preguntas por la misma persona y tú estás afuera de su oficina, la secretaria te contestará "He/She is IN his office". Podemos usar "in" or "at" con algunos lugares públicos, como por ejemplo: un restaurante, el teatro, el cine, etc. (teniendo en cuenta nuestro punto de referencia)

Prepositions of Time: at, in, on

We use:

• at for a PRECISE TIME
• in for MONTHS, YEARS, CENTURIES and SHORT/LONG PERIODS
• on for DAYS and DATES

at	in	on
PRECISE TIME	MONTHS, YEARS, CENTURIES and SHORT/ LONG PERIODS	DAYS and DATES
at 3 o'clock	in May	on Sunday
at 10.30am	in summer	on Tuesdays
at noon	in the summer	on 6 March
at dinnertime	in 1990	on 25 Dec. 2010
at bedtime	in the 1990s	on Christmas Day
at sunrise, at dawn	in the next century	on Independence Day
at sunset	in the Ice Age	on my birthday
at the moment	in the past/in the future/ in a while/ in a second/ in 2 minutes/ in 3 days/ in 4 hours	on New Year's Eve

Look at these examples:

• I have a meeting at 9am.
• The shop closes at midnight.
• Jane went home at lunchtime.
• In England, it often snows in December.
• Do you think we will go to Jupiter in the future?
• There should be a lot of progress in the next century.
• Do you work on Mondays?
• Her birthday is on 20 November.
• Where will you be on New Year's Day?

Notice the use of the preposition of time at in the following standard expressions:

Expression	Example
at night,at midday	The stars shine at night.
at the weekend	I don't usually work at the weekend.
at Christmas/Easter	I stay with my family at Christmas.
at the same time	We finished the test at the same time.
at present	He's not home at present. Try later.

¿At o on?

- At Christmas (en Navidad) va acompañado de at o de on. En este caso la diferencia es más cultural que gramatical pues en inglés británico suelen usar at y en estadounidense on.
Como ocurre con la palabra Christmas, hay ocasiones en las que en inglés americano se usa on y en británico at. En estos casos ambos son correctos y decidirse por una u otra depende del dialecto que quieras usar.
- At the weekend y on the weekend son ambos correctos.

Notice the use of the prepositions of time in and on in these common expressions:

in	on
in the morning	on Tuesday morning
in the mornings	on Saturday mornings
in the afternoon(s)	on Sunday afternoons
in the evening(s)	on Monday evening

Be careful!!!

When we say last, next, every, this we do not also use at, in, on.

• I went to London last June. (not in last June)
• He's coming back next Tuesday. (not on next Tuesday)
• I go home every Easter. (not at every Easter)
• We'll call you this evening. (not in this evening)

What is the difference between “on time” and “in time”?

On time = at the planned time; neither late nor early: puntual
Peter wants the meeting to start exactly on time.
He wasn't on time. Él no llegó a tiempo.
You are never on time. Nunca llegas a tiempo.



In time = with enough time to spare; before the last moment: a tiempo (para), con tiempo (para)
He would have died if they hadn't got him to the hospital in time.
He was in time for the meeting. Él llegó a tiempo para la reunión.
You are just in time for dinner. Llegas justo a tiempo para la cena.



What is the difference between “in the end” and “at the end”?
In the end = finally, after a long time: finalmente
In the end, I got a visa for Russia.



At the end = at the point where something stops: al final
I think the film’s a bit weak at the end.

More information about prepositions. IN/ON/AT

http://www.shertonenglish.com/resources/es/prepositions/prepositions-at-on-in-time.php
http://inglesparaprincipiantestutorrizo.blogspot.com.es/2012/06/uso-de-las-preposiciones-at-on-in.html
http://www.youtube.com/watch?v=8ZkdyMl9DL4

Para practicar:
http://www.abingles.com/ingles-basico/preposiciones-in-at-on.aspx

http://www.aulafacil.com/Ingejerc/Lecciones/Ejerc27.htm