На улице слякоть, поэтому лучше надеть старые ботинки.

Literally, на улице means on the street, but in everyday Russian it very often means outside / outdoors.

So:

• На улице холодно. = It’s cold outside.
• На улице дождь. = It’s raining outside.
• На улице слякоть. = It’s slushy outside.

Grammatically, улице is in the prepositional case because it follows на in a location meaning.

Слякоть means slush, muddy wet snow, or more generally messy wet weather, especially when snow and dirt mix on the ground.

It usually suggests:

• melting snow
• mud
• puddles
• unpleasant walking conditions

So it is not just rain and not just snow. It describes that dirty, wet, half-melted condition outdoors.

Russian often omits есть (is/are) in the present tense.

So:

• На улице слякоть. literally looks like Outside slush.
• Natural English: It’s slushy outside or There is slush outside.

This is very normal in Russian. Compare:

• Дома тишина. = It’s quiet at home.
• В комнате беспорядок. = The room is messy.

In the present tense, Russian often just puts the situation directly, without a verb like is.

Because поэтому means therefore / so / that’s why, and it connects the second clause to the first one.

The sentence has two parts:

• На улице слякоть
• поэтому лучше надеть старые ботинки

Russian normally separates these parts with a comma.

So the structure is:

• [situation], therefore [result/advice]

Поэтому means therefore, so, or that’s why. It introduces a consequence.

Here the logic is:

• It’s slushy outside
• therefore it’s better to put on old boots

It often comes near the beginning of the second clause:

• ... , поэтому ...

But Russian word order is flexible, so you may also see different arrangements in some contexts. Still, this position is the most neutral and common here.

Here лучше means it’s better to.

This is a very common Russian pattern:

• лучше + infinitive

Examples:

• Лучше подождать. = It’s better to wait.
• Лучше не спорить. = It’s better not to argue.
• Лучше надеть старые ботинки. = It’s better to put on old boots.

This лучше is not the adjective better agreeing with a noun. It is being used more like a predicative word expressing advice or preference.

The sentence is impersonal. Russian often leaves out the subject when it is general or understood from context.

So лучше надеть старые ботинки can mean:

• it’s better to put on old boots
• you’d better put on old boots
• one should put on old boots

In English, we usually need something like you or it, but Russian can leave that unsaid.

This is a very common question.

• надеть = to put on an item of clothing
• одеть = to dress someone

So:

• надеть ботинки = to put on boots
• одеть ребёнка = to dress a child

A useful memory trick:

• надеть что-то на себя = put something on yourself
• одеть кого-то = dress someone

So in this sentence, надеть старые ботинки is correct because you put boots on yourself.

Because it follows лучше in the pattern лучше + infinitive.

Russian often uses the infinitive after words expressing necessity, possibility, advice, or preference:

• можно войти = you may come in
• нужно идти = it’s necessary to go
• лучше надеть = it’s better to put on

So the infinitive is exactly what you would expect here.

Ботинки means boots/shoes and is plural because footwear is usually spoken of as a pair in Russian, just as in English.

Here it is in the accusative plural, because it is the direct object of надеть.

For inanimate plural nouns, the accusative usually looks the same as the nominative:

• nominative: ботинки
• accusative: ботинки

So the form does not change here.

Старые agrees with ботинки.

Since ботинки is:

• plural
• accusative
• inanimate

the adjective also takes the corresponding form:

• старые ботинки

For plural inanimate nouns, the accusative adjective form matches the nominative plural form, so you get старые.

Compare:

• старые ботинки = old boots
• новые туфли = new shoes

Because the sentence refers to a single complete action: putting the boots on.

• надеть = perfective, one completed act
• надевать = imperfective, process / repeated action / general habit

Here the meaning is basically: In these conditions, it’s better to put on old boots (this time).

If you used надевать, it would sound more like a habitual or repeated idea, for example:

• В такую погоду лучше надевать старые ботинки.
  In weather like this, it’s better to wear old boots.

So both can be possible in different contexts, but надеть fits the specific immediate recommendation very well.

Yes. Russian word order is flexible, although the given version is very natural and neutral.

For example, you could also say:

• На улице слякоть, поэтому старые ботинки лучше надеть.

That version puts more focus on старые ботинки.

But the original:

• На улице слякоть, поэтому лучше надеть старые ботинки.

sounds like the most straightforward way to express the idea.

Both are possible words, but they mean different things.

• ботинки = boots / ankle boots / sturdy shoes
• сапоги = taller boots

So the choice depends on what kind of footwear the speaker has in mind. The sentence is not mainly about tall winter boots; it is simply saying that older, less valuable footwear is a better choice in slushy weather.

It is mainly giving practical advice.

Russian often uses лучше + infinitive to sound fairly natural and not too direct. It can be softer than giving a direct command.

Compare:

• Надень старые ботинки. = Put on old boots.
  Direct instruction.
• Лучше надеть старые ботинки. = It’s better to put on old boots.
  Advice / recommendation.

So the sentence sounds practical and natural, not overly forceful.