Мы рылись в старье и разглядывали безделушки.

Because the subject is мы = we.

In the Russian past tense, verbs agree in gender/number, not in person the way present-tense verbs do. Since мы is plural, both verbs take the plural past form:

• рылись = we were rummaging / we rummaged around
• разглядывали = we were looking at / examining

So the -ли ending is the normal past plural ending.

The dictionary form is рыться, a reflexive verb.

Here, -сь is just the short reflexive ending attached after a vowel. After consonants, you usually see -ся; after vowels, often -сь:

• рыться
• рылись

In this verb, the reflexive ending does not mean a literal ourselves. It is simply part of the verb рыться, which means to rummage around, dig through things.

So рылись should be learned as the past plural form of the whole verb рыться.

It is the prepositional case after в.

The verb рыться commonly goes with в + prepositional, meaning to rummage in/through something:

• рыться в вещах = rummage through things
• рыться в мусоре = rummage through trash
• рыться в старье = rummage through old junk

The dictionary form of the noun is старьё. After в, it changes to the prepositional form старье.

Because the noun changes form by case.

• dictionary form: старьё
• after в here: в старье

So this is not just a spelling variant; it is a grammatical case form.

A separate point: in Russian writing, the dots over ё are often omitted in many words. But in this sentence, старье is also the correct case form anyway.

Grammatically, старьё is singular.

But semantically, it is a collective/mass noun: it refers to a pile or mass of old stuff, junk, worn-out things, secondhand odds and ends.

This is similar to English words like junk or old stuff, which are grammatically singular but refer to many objects.

So в старье means something like in the old junk / among the old stuff.

It is the accusative plural, because it is the direct object of разглядывали.

Dictionary form:

• singular: безделушка
• plural: безделушки

Since безделушки are inanimate, the accusative plural looks the same as the nominative plural:

• nominative plural: безделушки
• accusative plural: безделушки

So in this sentence, разглядывали безделушки means were examining trinkets/knick-knacks.

Because разглядывать is a transitive verb. It takes a direct object in the accusative case.

So Russian says:

• разглядывать безделушки

not

• разглядывать на безделушки

This is different from some English patterns where look at needs a preposition. Russian разглядывать already includes the idea of looking at carefully, so it takes the object directly.

Both рылись and разглядывали are imperfective. That fits the sentence because it describes an ongoing scene or process, not a single completed result.

It gives the feeling of:

• we were rummaging
• and looking over / examining

This is very natural when narrating background action or describing what people were doing for some time.

If perfective verbs were used, the sentence would sound more like completed, bounded actions, which is not the main idea here.

Смотреть just means to look.

Разглядывать means to look at closely, examine, inspect with interest or attention.

So:

• смотрели безделушки would not be normal Russian
• смотрели на безделушки = were looking at the trinkets
• разглядывали безделушки = were studying/examining the trinkets closely

So разглядывали is more vivid and more specific than just looked at.

Yes, somewhat.

Especially старьё has a casual, everyday feel and can sound slightly dismissive, like old junk or old stuff rather than a neutral formal word.

The whole sentence sounds natural in storytelling or conversation:

• Мы рылись в старье и разглядывали безделушки.

It feels like a scene from a flea market, attic, antique shop, or box of old вещей, not formal written prose.

Yes. Russian word order is flexible, and changing it can shift emphasis.

The given order is quite natural and neutral:

• Мы рылись в старье и разглядывали безделушки.

You could move things around for emphasis, for example:

• В старье мы рылись и разглядывали безделушки.

But that sounds more marked. For a learner, the original sentence is the best neutral model to follow.