Learn Hardcore Spanish (Spain): Sin que nadie lo note, mi amigo recoge las sillas y quita el polvo. - Without anyone noticing, my friend picks up the chairs and removes the dust.

Because sin que (“without”) triggers the subjunctive in the subordinate clause. It expresses something that should not happen or is prevented: Sin que nadie lo note = “without anyone noticing.” Hence, note (present subjunctive), not nota (indicative).

Could I say Sin que nadie lo nota?

No. After sin que, you need the subjunctive: note. Use the indicative (nota) only in independent or factual clauses, not in this type of purpose/contingency clause.

What about past time? Should it be notara?

If the main action is in the past, you typically use the past subjunctive:

Present: Mi amigo recoge… sin que nadie lo note.
Past: Mi amigo recogió… sin que nadie lo notara.

What does lo refer to in Sin que nadie lo note?

It can refer to:

A neutral “it/that” (the change or the action he’s doing). This is the most natural reading here.
Or “him” (mi amigo), i.e., “without anyone noticing him.” Spanish allows that ambiguity with lo.

Is lo required? Can I drop it and say Sin que nadie note?

With notar, a direct object is expected. If you drop lo, the sentence sounds incomplete unless you add something:

Sin que nadie lo note (it/him)
Sin que nadie note nada (anything)
Sin que nadie note que… (+ clause)
A very common alternative is impersonal: Sin que se note (“without it being noticeable”).

Could I use le instead of lo?

If you mean “it/that,” only lo works.
If you mean “him,” standard Spanish prefers lo, but in Spain you will hear leísmo: Sin que nadie le note (accepted by the RAE for masculine persons). Outside leísta areas, stick to lo.

Why isn’t there a no with nadie? Should it be sin que no nadie…?

No. Sin already carries the negative meaning. In Spanish, negative words like nadie can appear without no after a preposition or when placed before the verb: sin que nadie… is correct. You would use no if nadie comes after the verb: No lo nota nadie.

Why is note singular with nadie?

Because nadie (“nobody”) is grammatically singular. So the verb is third-person singular: nadie lo note.

Why do we need que? Can I say Sin nadie lo note?

No. Sin que is required before a finite clause with its own subject and conjugated verb. Use bare sin only with a noun/gerund/infinitive:

Different subject: Sin que nadie lo note.
Same subject: Sin notarlo, sin notar nada, etc.

What’s the difference between Sin que nadie lo note and Sin que se note?

Sin que nadie lo note highlights “nobody” as the agent who could notice it.
Sin que se note is impersonal/passive: “without it being noticeable.” Both are fine; the second is more neutral and very idiomatic.

Does notar mean the same as darse cuenta or advertir?

Often, yes, but nuances differ:

notar: to perceive/notice (often sensory or evident change).
darse cuenta (de que): to realize/notice (the cognitive act; very common).
advertir: to notice/become aware of; also “to warn” in other contexts; slightly more formal.
Here you could also say: Sin que nadie se dé cuenta.

What exactly does recoger las sillas mean?

In Spain it usually means “to pick up/collect/put away the chairs” (e.g., stack them, return them to their place) as part of tidying. It’s broader than just lifting them; it implies organizing/clearing up.

Why recoge and not something like coge or levanta?

recoger = pick up/collect/put away/tidy. Best fit for cleaning up.
coger in Spain can mean “to take/pick up,” but avoid it in much of Latin America where it’s vulgar.
levantar = to lift (doesn’t imply tidying).
So recoge is the idiomatic choice here.

Is quita el polvo the standard way to say “to dust” in Spain?

Yes. Common options in Spain:

quitar el polvo (very standard)
limpiar el polvo (also common)
sacudir el polvo (shake/beat dust off, e.g., a rug)
Avoid plural unless you mean “powders” (cosmetics): it’s el polvo as a mass noun.

Why is it el polvo, not just polvo?

With mass/generic nouns in household chores, Spanish typically uses the definite article: quitar el polvo, poner la mesa, pasar la aspiradora. Saying quitar polvo is odd in this sense.

Any pronunciation/spelling tips for recoger?

Yes. It’s re-CO-ger. In the yo form, the spelling changes to keep the sound: yo recojo (not “recogo”). Third-person forms like recoge keep the g.

Is the comma after Sin que nadie lo note required?

Yes, when a subordinate clause comes first, Spanish normally sets it off with a comma: Sin que nadie lo note, mi amigo… If you move the clause to the end, no comma is needed: Mi amigo… sin que nadie lo note.

Do both verbs share the same subject?

Yes. Mi amigo is the subject of both recoge and quita: “my friend picks up the chairs and dusts.” The subject of note is nadie within its own clause.