Prepositions

You will already know a little about this area if you have followed the guide to word class. You learnt there that prepositions are a class of closed system items (meaning that there are a finite number in the language).

Definition

Prepositions in English usually come before a noun and tell us the relationship between two things. For example, The man was standing on the street tells us the relationship between stand and street.
Sometimes a preposition can come before a verb -ing clause in e.g., by using this website.

They are difficult to learn for a number of reasons.

They do not readily translate between languages so, for example, we have the English She took it off the table being in German She took it from the table and so on.
It is also the case that a preposition in one language may be translated a number of ways in English depending on the context and vice versa.
Some languages do not use prepositions at all, preferring to change verbs or to insert post-positions such as She walked the road along. (Note that English sometimes does this, too, in things like The whole day through but it is unusual.)
Prepositions perform multiple tasks so we have I met her at the station at 1 o'clock where at is performing two different, if related, functions.
Prepositions need not be single words such as on or out. There are many which are two words such as apart from or next to and some like as well as or as soon as which are three words long.
There is a certain randomness about the use of prepositions in many languages and English is no exception. We say, e.g., in the morning, in the evening and in the afternoon but at night.

The prepositional phrase

A prepositional phrase consists of the preposition and its complement (usually a noun or pronoun but sometimes a verb phrase with -ing). Because prepositions are structural or functional words, they carry no meaning in themselves. The word at means nothing but at the bus stop does carry meaning. A prepositional phrase is generally the target of teaching, therefore.

Common prepositions

A list of all the prepositions in English runs to over 200 words but many are rare or obsolete words such as athwart, betwixt and pursuant to. Except at quite advanced levels, these are probably best left alone.
There are far fewer common prepositions which form the majority of prepositional phrases. Think of 10 and then click for a list.

about
above
across
ago
at
before
below

beside
by
for
from
in
into
next to

of
off
on
onto
out of
over
past

since
through
till
to
towards
under
until

Not only are these prepositions the commonest ones, they are among the commonest words in English. It is hard to imagine a written or spoken text in which some don't appear.
(Note: ago is in this list but many would categorise the word as an adverb rather than here where it forms the only example of a post-position.)

Marginal prepositions

Some words, often verbs, can act as prepositions but are often categorised as something else (generally as non-finite verbs or even adjectives). Here are some examples:

Following my instinct, I tried change the switch
Regarding the information you gave, I made my decision
We'll have to wait, pending the outcome of the meeting.
Given the fact that he is so late, I think we should start.
Including / Excluding the money we spent on petrol, the trip was cheap.
Six minus / plus / times / over three is ....

Making sense of prepositions

The two fundamental categories of prepositions are time and place.

Some of the prepositions above can naturally act in both ways (at 6 o'clock, at the bank), some only refer to place (beside the road) and some only to time (since 1940). Can you categorise them? Click when you have.

Time only	Place only	Both
since (the war, 4 o'clock) until (7, dawn) for (two hours, weeks) till (midnight) (six months) ago	through (the park) beside (the river) from (London) into (the box) next to (the house) off (the road, the top) onto (the table) out of (the box) above (the airport) across (the street) below (the plane) of (a tramp)	on (Monday, the table) over (a week, the town) past (four o'clock, the door) by (my side, 6 o'clock) in (an hour, the class) to (the end of the day, the corner) under (a month, the table) about (the house, twenty minutes) at (the corner, 6:15) before (4 o'clock, me) towards (the station, dawn)

OK. Now we can look at each group separately and identify the important issues.

Prepositions of time

Preposition	Use	Example
on	days	on Monday, on my birthday
in	months time of day year period of time	in January in the morning in 1998 in two years
at	night weekend / holidays point in time	at night (time) at the weekend, at Christmas at 4 o'clock
since	from a point in time	since then, since 2009
for	a period of time	for a week
ago	post-positional for period of time	two years ago
before	earlier than a point in time	before 9
to / till / until	showing start and finish duration	from now to eternity until the end of the day
past / to	time telling	ten past, quarter to
by	at the latest	by 10 o'clock at least

Issues

since, for and ago: cause serious problems because their concepts vary across languages. Errors such as I have worked since 4 hours are common.
on, in and at: cause problems for similar reasons. Teaching in the morning as a single item is a solution rather than asking learners to match prepositions to time expressions.
by: is frequently used with future perfect forms (such as She will have finished by 6). In many languages until is synonymous so you will hear Be here until 6 o'clock (when by or before is meant).

Now, can you come up with a similar list for prepositions of place? Click here when you have.

Prepositions of place

Preposition	Use	Example
on	attached for surfaces sides public transport media	on the wall on the table on the right, on the front on the bus on TV
in	buildings private transport within	in the house in a car in a book, in a box
at	exact place (relatively) events work places	in the station, at platform 6 at the party at work, school
by, next to, beside	lateral proximity	by me next to her beside Mary
under	lower than (often covered)	under the road
over	higher than more than from one side to the other	over my head over 21 over the table
above	higher than	above the city
across	from one side to the other on the other side	(walk) across the road (be) across the road
through	between two limits	through the park, tunnel etc.
to	movement towards	give it to me to London
into	movement to inside	into the room
towards	movement in direction of	towards me
onto	movement resulting in on	onto the table
from	movement away	from the garden a present from her
out of	movement to the outside	get it out of the envelope get out of the car
off	downward or away movement	take it off the wall get off the bus

Issues

relative exactness: in and at are often used in tandem to say that one position is more exact than the other. For example, She is in London tomorrow and arrives at Paddington. When she's in the station, she'll ring and I'll pick her up at the entrance. (Compare: I'll see here in the morning at 11.)
above, over, below, under: sometimes cause problems because above and below imply relative height but over and under often imply position exactly. So we get, The plane flew below 5000 feet directly over the town. I couldn't see the key because it was under the paper. In future, I'll hang it on the hook over the door.
movement: is handled differently in many languages so expect error such as I saw it onto the table or I looked into my pockets.
Additionally, onto and into only imply movement but on and in can imply position or movement.
Out of usually implies movement but is often used by learners for position so we get It's out of the box rather than It's outside the box. (There are also times when out of does refer to position: I left it out of the house.)

Here's a diagrammatic summary:

preposition grid
Source: adapted from Quirk and Greenbaum (1973:146)

This page is available as a PDF document and there are more advanced guides to prepositions of place and prepositions of time in the in-service training section. There is also a more advanced guide to prepositional phrases in the in-service training section of this site.

Click here for a list of prepositions in English.

There is a short video on this site intended to help elementary learners understand some of the issues mentioned here.
There is another video in the teachers section presenting the 7 meanings of over.

Take a short test.

Reference:
Quirk, R & Greenbaum, S, 1973, A University Grammar of English, Harlow: Longman