Cierro la ventana en la noche.

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Breakdown of Cierro la ventana en la noche.

• la ventana: the window
• la noche: the night
• cerrar: to close

Questions & Answers about Cierro la ventana en la noche.

Why is it cierro instead of another form like cierres or cerro?

In Spanish, cierro is the first-person singular (yo) present tense form of the verb cerrar (to close). The verb undergoes an e → ie stem change, so cerrar becomes cierro in the yo form.
• cierres would be the tú form (you close).
• cerro (with just one 'r' in the middle) actually means "hill" and is unrelated to the verb cerrar.

Why do we say la ventana instead of dropping the article?

Spanish typically uses a definite article (el, la, los, las) before nouns when referring to a specific item, or one that is known to both the speaker and listener. In English, you might say I close the window, but in Spanish it is even more common to use la or el to talk about everyday objects that are understood to be specific (like the window at home). So we say la ventana rather than just ventana.

Can we say por la noche instead of en la noche, and is there a difference?

Yes, por la noche is very commonly used in many Spanish-speaking regions to mean "at night," whereas en la noche can sound slightly more literal or specific. In practice, both are generally understood as "at night," but por la noche might be heard more frequently, especially in everyday conversation.

Is the position of en la noche flexible in this sentence?