La bolsa de lavandería protege la ropa.

Because bolsa and ropa are both feminine singular nouns in Spanish, so they take the feminine singular article la.

• la bolsa = the bag
• la ropa = the clothes / clothing

This grammatical gender is part of the noun itself. It does not mean the objects are feminine in any real-world sense.

In Spanish, ropa is usually treated as a singular collective noun. It refers to clothing in general, even though English often uses the plural word clothes.

So:

• la ropa = clothing / clothes
• not las ropas in normal everyday use

You may sometimes see ropas, but that is much less common and usually sounds more specific, literary, or regional.

De lavandería means something like for laundry or used in the laundry process.

Literally, de often means of, but in Spanish it is also commonly used to connect nouns the way English uses noun modifiers:

• bolsa de lavandería = laundry bag
• máquina de café = coffee machine
• taza de té = tea cup

So bolsa de lavandería is not saying the bag belongs to a laundromat. It is describing the bag’s purpose or type.

Because protege is the conjugated verb, while proteger is the infinitive.

• proteger = to protect
• protege = protects / does protect

In this sentence, the subject is la bolsa de lavandería, which is third person singular, so the verb must match:

• La bolsa de lavandería protege... = The laundry bag protects...

The subject is la bolsa de lavandería because it is the thing doing the action of protecting.

A simple way to check:

• Ask: What protects the clothes?
• Answer: La bolsa de lavandería

So:

• Subject: la bolsa de lavandería
• Verb: protege
• Direct object: la ropa

Spanish usually does not need a subject pronoun when the subject is already stated.

English often says:

• The laundry bag protects the clothes

Spanish does the same:

• La bolsa de lavandería protege la ropa

And even if the subject were not stated, Spanish can often leave out pronouns because the verb form gives the information:

• Protege la ropa = It protects the clothes / He protects the clothes / She protects the clothes, depending on context

This is very normal in Spanish.

In standard Spanish, when speaking about a specific noun in a general, natural way, the article is often used where English might not use one.

So:

• protege la ropa = protects the clothes / protects clothing

Saying protege ropa is not the usual full-sentence phrasing here. It could appear in advertising, labels, or very compressed style, but protege la ropa sounds more normal as a complete sentence.

They are different nouns:

• bolsa usually means bag, sack, or pouch
• bolso usually means handbag, purse, or a type of bag worn/carried personally

In this sentence, bolsa makes sense because a laundry bag is a bag or sack used for washing or holding clothes.

Lavandería is pronounced roughly like lah-bahn-deh-REE-ah in Latin American Spanish.

The written accent on í shows that the stress falls on that syllable:

• la-van-de-rí-a

Without the accent mark, Spanish stress rules would suggest a different pronunciation. So the accent mark is important for showing the correct stress.

Sometimes, yes, depending on context.

Lavandería can mean:

• laundry
• laundry service
• laundromat
• a place or service related to washing clothes

In bolsa de lavandería, it does not necessarily mean a public laundromat. It more generally describes a laundry bag.

Yes. Depending on context, Spanish offers other natural options, such as:

• La bolsa para lavar ropa protege la ropa.
• La bolsa de lavado protege la ropa.
• La bolsa para la lavandería protege la ropa.

But La bolsa de lavandería protege la ropa is a natural, compact way to say it.

The exact best choice can depend on what kind of bag you mean:

• a bag for carrying dirty clothes
• a mesh bag for washing delicate items
• a bag used at a laundromat or laundry service

Yes, but this sentence uses the most normal word order in Spanish:

• Subject + verb + object
• La bolsa de lavandería
  • protege
    • la ropa

Spanish can sometimes change word order for emphasis, but the standard order here is clear and natural. For a learner, this is the best pattern to follow.