Learn Spanish (Spain): Ellos leen el correo y escriben la carta. - They read the mail and write the letter.

In the present tense, regular -ir verbs and -er verbs share almost the exact same endings. For the ellos (they) form, both groups use the ending -en. To conjugate it, you drop the -ir from escribir and add -en to make escriben.

Why does leen have two 'e's in a row?

The verb for 'to read' is leer. To make the 'they' form, you drop the -er ending, which leaves you with just the root le-. Then you add the ellos ending for -er verbs, which is -en. Putting them together gives you leen.

Can I leave out the word Ellos at the start of the sentence?

Yes, you can just say Leen el correo y escriben la carta. Because the verbs leen and escriben have endings that already tell us 'they' are doing the action, the pronoun Ellos is optional. You would only include it to add emphasis or to clarify exactly who is doing the action if it was not already clear from the conversation.

What is the difference between el correo and la carta?

El correo is a general term for the mail or the post, and it can also refer to the post office or an email. La carta is a specific physical letter that you put in an envelope. In this sentence, they are reading their general mail and writing a specific letter.