Prepositions are small words that connect elements in a sentence. They are essential because they provide additional details about the sentence.

We use prepositions of time to locate an event in a time frame.

Prepositions of time don’t stand alone but act with other elements of the sentence to create what we can call prepositional phrases: at, on, in and by.

• At
  • Everyday at 7.00 clock I can see the stars.
  • He is going to the forest at Easter.
  • At weekends we take the dogs for a walk.
• On
  • On Sundays, I usually relax with my friends by going to the coast.
  • She was born on the 1st of September in 1997.
  • The island sank on Sunday morning.
• In
  • I always travel to famous forests in Finland in November.
  • In autumn it always rains.
  • In the evening the horses started to run.
• By
  • Please, send me those tickets by Monday.
  • She has to finish her world map by next week.
  • Is Maria still in the garden? Yes, she will be back by evening.

Prepositions of time make it possible to locate an event in a specific moment or period.

• At
  • Exact times (the moment, sunrise, noon, night, midnight, hours);
  • Special holiday periods (Christmas*, Easter…);
  • Weekend*.
• On
  • Days of the week (Monday, Saturday, Wednesday…);
  • Dates;
  • Specific part of the day (on Sunday morning).
• In
  • Months, years, centuries;
  • Seasons;
  • The morning, the afternoon, the evening.
• By
  • Time-limited actions;
  • Projects with deadline;
  • Time of someone´s return.

*In American English you can find on instead of at.

Prepositions of time are used to locate the event in a time context.

The main prepositions of time are:

• At: for exact times, special holiday periods and weekend;
• On: days of the week, dates and specific part of the day;
• In: months, years, seasons, centuries, the morning, the afternoon and the evening;
• By: time-limited actions, projects with deadline and time of someone´s return.

For example:
— “I will go to my grandparents’ house at Christmas.”
— “I will go to my grandparents’ house on 25th of December.”
— “I will go to my grandparents’ house in December.”
— “I will return from my grandparent´s house by December.” 

NOTE: In American English you can find Christmas and weekend with on instead of at.

Let’s revise this content within the {Form} section. Take a look at the {Example} section that shows its use within a context.