The most common word for ‘when’ is ‘cuando’, but you can also use the contraction ‘al’ (a + el) to indicate when something happens.

Check out some examples:

Hay error al enviar los mensajes por Outlook. – There is an error when you send messages using Outlook.

Al enterarse de lo que había sucedido, se puso a llorar. – When she found out what had happened, she started crying.

Tiene Ud. que tomar las píldoras al amanecer y al acostarse. – You have to take your pills at dawn and when you go to bed.

Al escuchar el himno nacional, las personas quitaron el sombrero. – On hearing the national anthem, people took off their hats.

Al entrar en el aula, el maestro se dio cuenta de que había pocos alumnos. - As he walked into the classroom, the teacher realized there were few students.

Would you know how to say these sentences (if possible), using the word ‘cuando’? If so, write a comment!