Prepositions link nouns, pronouns, and gerunds to the rest of the sentence. They show relationships of place, time, direction, manner, cause, possession, and fixed patterns. In English, a preposition normally comes before its object, and the object is usually a noun, pronoun, or gerund. Correct use of prepositions also depends on set expressions and verb or adjective patterns, so meaning and grammar work together.

Prepositions of place show where something is located. Prepositions of Place covers these patterns in more detail, including fixed expressions for location and position. Some place phrases are highly regular, while others are idiomatic and must be learned as units.

Idea	Example
Use in to show something is inside a space.	The keys are in the box.
Use on to show something touching a surface.	The book is on the table.
Use at to show a point, address, or general location.	She is at home.
Use in front of to show a position before something.	The car is in front of the house.

Prepositions of time show when something happens. Prepositions of Time explains the most common time patterns, including parts of the day, days, months, and longer periods. British English often uses at the weekend, while American English often uses on the weekend.

Idea	Example
Use at for specific times and clock points.	The meeting starts at 5pm.
Use on for days and dates.	We leave on Monday.
Use in for months, seasons, and longer periods.	She was born in July.
Weekend use varies by region.	We relax at the weekend.

Prepositions of direction show movement toward a place or into it. Prepositions of Direction develops the difference between arriving at a place, entering it, and moving onto a surface. These forms are important because direction words often change the meaning of the sentence.

Idea	Example
Use to to show movement toward a destination.	They go to school.
Use into to show movement from outside to inside.	He walked into the room.
Use onto to show movement to a surface.	The box fell onto the floor.
Regional transport use may vary.	She travels on the bus.

Prepositions can show the way something is done. Manner and instrument are often expressed with by, with, and like, depending on whether the focus is transport, an object used, or comparison. Idiomatic Prepositions includes many fixed choices that cannot be changed freely.

Idea	Example
Use by for transport or method.	They travel by train.
Use with for an instrument or tool.	She cut the cake with a knife.
Use like for similarity or manner.	He speaks like a teacher.
Use by to show the means used to send or deliver something.	The letter arrived by post.

Prepositions can also express reason, purpose, and relation. For and because of often point to purpose or cause, while due to is common in formal descriptions of reason. Prepositional Phrases shows how these words combine with nouns and noun phrases to form larger units.

Idea	Example
Use for to show purpose or intended use.	He left for work.
Use because of to show a cause.	The train was delayed because of traffic.
Use due to in formal writing for a cause or explanation.	The delay was due to rain.
Use for to show benefit or intended receiver.	This gift is for you.

The preposition of shows possession, relation, and partitive meaning. It often connects one noun to another noun that names the whole, the owner, or the part being described. This pattern is common in formal and everyday English, especially when one noun depends on another noun to complete the meaning.

Idea	Example
Use of to show possession or relation between nouns.	The title of the book is long.
Use of to show a part of a whole.	A piece of cake was left.
Use of in noun phrases that name a specific part or feature.	The cover of the report is blue.

Many verbs and adjectives require a specific preposition after them, and the object must follow that preposition. Idiomatic Prepositions is especially useful for these patterns, because the choice is often fixed rather than optional. Some patterns are followed by a gerund, not an infinitive, so the form after the preposition matters as well.

Idea	Example
Use interested in after adjectives of feeling or reaction.	She is interested in history.
Use depend on after verbs that require a preposition.	We depend on help from others.
Use look forward to before a gerund.	I look forward to seeing you.
Use object forms after prepositions.	Between you and me, it is secret.

Some prepositions belong to fixed phrases that should be learned as complete units. These phrases often behave like single adverbial or prepositional expressions, and the preposition cannot be replaced by a near synonym without changing the meaning. Prepositional Phrases provides a wider view of these expressions in grammar and usage.

Idea	Example
Use in front of as a fixed phrase for position.	The bike is in front of the shop.
Use on behalf of as a fixed phrase for representing someone.	She signed on behalf of the team.
Learn fixed phrases as whole units.	The answer depends on context.