Prepositions often come at the ends of clauses in English. This happens in several kinds of structure:

a) questions beginning what, who, where etc.

• What are you looking at?
• Who did you go with?
• Where did you buy it from?

b)    relative clauses

• There's the house (that) I told you about.
• You remember the boy I was going out with?

IN

Use 'in' months and years and periods of time:

• in January
• in 1978
• in the twenties

Use 'in' a period of time in the future:

• in a few weeks
• in a couple of days

AT

Use 'at' with precise time:

• at six o'clock
• at 10.30
• at two p.m.

ON

Use 'on' with days of the week:

• on Monday
• on Fridays

Use 'on' with specific calendar days:

• on Christmas day
• on October 22nd

Notes to remember

in the morning / afternoon / evening - at night

We say in the morning, afternoon or evening BUT we say 'at night'

Explanation of when to use the prepositions for, while and during.

FOR
Use 'for' with a period of time to express the duration or 'how long' something has happened:

• for three weeks
• for many years

WHILE
Use 'while' plus a verb form:

• while I was watching TV
• while I lived in New York

DURING
Use 'during' with a noun to express 'when' something happens:

• during class
• during my vacation
• during the discussion

Rules for using the prepositions - in / at / to / nothing - prepositions of place and movement.

IN
Use 'in' with static (non-movement) verbs and cities, countries, states, etc.:

• stay in the USA
• work in New York

AT
Use 'at' with static (non-movement) verbs and places:

• at the cinema
• at work
• at home

TO
Use 'to' with verbs of movement such as go, come, drive, etc.:

• go to work
• drive to California

IMPORTANT NOTES

The use of “nothing”

With verbs of movement and the noun 'home'

• He went home.
• They drove home.

With the verb 'visit'

• She visited France last summer.

IN

Use 'in' with spaces:

• in a room / in a building
• in a garden / in a park

Use 'in' with bodies of water:

• in the water
• in the sea
• in a river

Use 'in' with lines:

• in a row / in a line
• in a queue

How to use IN ON AT in expressions of time

Within means not outside a place.

Pattern: be + within + noun
Those schools are within the county jurisdiction.
There is too much commotion within the building.

How to use the preposition "about" correctly?

About identifies a topic.

Pattern 1: noun + be + about + noun
This book is about prepositions.