On, At and In: Prepositions in English A preposition is a word that links a noun, pronoun or phrase nominal to the other part of the sentence, to show direction, place, time or to introduce an object. As already stated, prepositions show direction, place, time, or some object and, although they do not have rules of use, they do have some to use them that help us learn better. For example: On – For days and dates, surface, a part of the body / On, no, na – dias e dates, surfaces and body part. At – For a precise time, for indicate a place / Em, no, na – exact time, indicate place. In – For months, years, centuries and long periods, enclosed space / Em, in, na – months, years, centuries, long periods and spaces closed/specific. Let's take a look at the examples using the prepositions: On, At and In. / Let's take a look at the examples using the prepositions: On, At and In. on For days and date: / For days and dates My family will arrive on Friday. / My family arrives on Friday. He was born on the 20 th day of January in 1983. / He was born on the 20th of January 1983. I'll be there on Christmas Day. / I'll be there for Christmas. For a surface: / For surface They're putting their name on the wall. / They're putting the names them on the wall. The notebook is on the table. / The book is on the table. Let's lie down on the floor. / Let's lie down on the floor. For a part of the body: / For a part of the body He kissed me on my forehead. / He kissed me on the forehead. She's wearing a pretty ring on her finger. / She's wearing a beautiful ring on her finger. You can put your hand on my shoulder. / You can put your hand on my shoulder. at For a precise time: / For an exact time We will meet you at 3 p.m. / We'll meet you at 3 pm. The limousine will stop here at 7:35 a.m. / The Limousine will stop here at 7:35 in the morning. I want you here at dinnertime. / I want you here by dinnertime. Used to indicate a place: / Used to indicate a place It's at the corner of Redmond Avenue with Freedon Street. / stay in corner of Avenida Redmond and Rua Liberdade. There is a kids party at the mall today. / There's a kid's party at the mall today. There are a thousand people at the club. / There are a thousand people in the club today. in For months, years, centuries and long periods: / For months, years, centuries and long periods. I love read newspapers in the morning. / I love to read the newspaper in the morning. We have a long holiday in the summer. / We have a long holiday in summer. The new season will start in July. / The new season will start in July. For enclosed space: / . I'll wait for you in the garden. Let's meet in France. / He looked at me in the eyes.