Learn Spanish (Latin America): Cuando termines de apretar los tornillos, lo volveremos a intentar. - When you finish tightening the screws, we will try again.

The phrase volver a followed by an infinitive (here, intentar) is a very common way to express doing an action again. Instead of using a separate word for 'again' like otra vez, Spanish uses volveremos a intentar, which literally translates to 'we will return to try'.

Why is lo at the very beginning of lo volveremos a intentar?

Lo is the direct object pronoun meaning 'it'. When you have a conjugated verb paired with an infinitive (like volveremos a intentar), you have two choices for where to place the pronoun. You can place it before the conjugated verb (lo volveremos a intentar) or attach it directly to the end of the infinitive (volveremos a intentarlo). Both are perfectly correct and mean the exact same thing!

Why is the verb termines in the subjunctive here instead of the indicative terminas?

We use the subjunctive termines because cuando (when) is introducing an action that hasn't happened yet. In Spanish, when you talk about a pending future event after time words like cuando, you must use the subjunctive. If you were talking about a habitual action ('Whenever you finish...'), you would use the indicative.

Why do we need the word de in termines de apretar?