Guarda el tapón de la botella en el cajón para no perderlo.

Guarda is the tú imperative of guardar, so it means keep / put away / store as a command or instruction addressed to one person.

• guardar = the infinitive, to keep / to store
• guardas = you keep, a statement
• guarda = keep! / put it away!, a command

So the sentence is telling someone what to do.

Here guardar means something like:

• put away
• keep
• store
• put somewhere safe

It does not necessarily mean guard in the English sense of protecting something physically. In this sentence, the idea is put the bottle cap in the drawer so you do not lose it.

This is the normal Spanish way to say the bottle’s cap or the cap of the bottle.

Spanish often expresses possession with:

noun + de + noun

So:

• el tapón de la botella = the cap of the bottle = the bottle cap

This is very common and natural in Spanish.

Spanish uses definite articles more often than English does.

In this sentence:

• el tapón = the cap
• la botella = the bottle
• el cajón = the drawer

English might sometimes use fewer articles or use possessives instead, but Spanish often prefers the article when the thing is identifiable from the context.

For example, English might say Put the bottle cap in your drawer, but Spanish can naturally say en el cajón if the drawer is understood from the situation.

En is used because it means in or inside here:

• en el cajón = in the drawer

If you say a, that usually suggests movement to a destination, but with containers or enclosed places, Spanish often uses en to express where something ends up being placed.

Also, a el normally contracts to al, but al cajón would not sound right here for the intended meaning. The natural phrase is en el cajón.

This part expresses purpose:

• para = in order to / so as to
• no = not
• perderlo = to lose it

So para no perderlo literally means:

in order not to lose it

This is a very common Spanish pattern:

para + infinitive

Examples:

• para estudiar = to study / in order to study
• para no olvidarlo = so as not to forget it

Because lo refers to el tapón, which is masculine.

• el tapón → masculine singular → lo
• la botella → feminine singular → la

So the sentence means so as not to lose the cap, not so as not to lose the bottle.

This is an important clue for understanding what the pronoun refers to.

In Spanish, object pronouns can attach to an infinitive.

So:

• perderlo = to lose it

This is completely normal after para.

You cannot say:

• para no lo perder ✘

The natural options are:

• para no perderlo
• para no perder el tapón

Both are correct, but the version with the pronoun sounds more natural once the object has already been mentioned.

Because the subject is the same person in both parts of the sentence.

• Guarda... = You put it away
• para no perderlo = so that you do not lose it

When the subject is the same, Spanish usually uses:

para + infinitive

If the subject changes, Spanish normally uses:

para que + subjunctive

For example:

• Guarda el tapón para no perderlo.
  = Put the cap away so you do not lose it.

But:

• Guarda el tapón para que tu hermano no lo pierda.
  = Put the cap away so that your brother does not lose it.

No, Spanish word order is fairly flexible, although this version is very natural.

The sentence as given:

Guarda el tapón de la botella en el cajón para no perderlo.

sounds clear and neutral.

You could also hear:

• Guarda en el cajón el tapón de la botella para no perderlo.

That is possible, but the original order is smoother and more common for a simple instruction.

The accent mark shows where the stress falls:

• ta-PÓN

Without the accent, Spanish spelling rules would make you expect a different stress pattern.

So the written accent helps you pronounce it correctly and also tells you it is a separate word from any hypothetical unaccented form.

In practice, no. It most naturally refers to el tapón.

Why?

1. Grammar:
   lo is masculine singular, so it could match el tapón or el cajón, but not la botella.

2. Meaning:
   The purpose clause para no perderlo makes most sense with tapón. You put the cap in the drawer so you do not lose the cap.

So even though Spanish pronouns can sometimes be ambiguous, here the intended meaning is very clear.