En algunos casos, las preposiciones son bastante difíciles de utilizar, así que os he hecho un cuadro para que os ayude y podáis aprender (y luego poner en práctica)
Ejemplos:
In September - In summer - In 2015 - In the XXth Century - In the term - In the morning
In Zaragoza - In the hospital - In Gran Vía street
On Thursday - On 22nd September - On Christmas Eve - On Tuesday afternoon
On the 7th floor - On Ebro river - On the Internet
At 19:00 - At dinner - At Christmas - At the medieval age - At the cinema - At Sonia's house
At home - At 35 Downtown street - At Logroño
English exercises
English hilfen
My English pages
To learn English
Eamus