इस सतह पर तेल की परत है।

Hindi usually places the main verb at the end of the sentence, so है comes last.

A natural breakdown is:

• इस सतह पर = on this surface
• तेल की परत = a layer of oil
• है = is

So the structure is roughly:

[location] + [thing] + [is]

That is very normal in Hindi.

Here is a word-by-word breakdown:

• इस = this
• सतह = surface
• पर = on
• तेल = oil
• की = of
• परत = layer
• है = is

So literally, it is something like:

On this surface, oil-of layer is.

More natural English: There is a layer of oil on this surface.

This is because Hindi demonstratives like यह change form before a postposition.

• यह = this
• इस = oblique form of यह

Since सतह is followed by the postposition पर, the noun phrase goes into the oblique form:

• यह सतह = this surface
• इस सतह पर = on this surface

This is a very common pattern in Hindi.

Hindi uses postpositions, not prepositions.

In English:

• on the surface

In Hindi:

• surface on → सतह पर

So पर means on, but it comes after the noun phrase it belongs to.

This is one of the most important word-order differences between English and Hindi.

Because परत is a feminine noun, and का / की / के must agree with the noun that comes after it.

Here:

• तेल = oil
• परत = layer
• परत is feminine singular

So the correct form is:

• तेल की परत = layer of oil

Compare:

• राम का घर = Ram's house (घर is masculine singular)
• सीता की किताब = Sita's book (किताब is feminine singular)

So in तेल की परत, की agrees with परत, not with तेल.

Yes, literally it is something like oil's layer, but in natural English we translate it as a layer of oil.

Hindi often uses the का / की / के construction in places where English uses of.

So:

• तेल की परत = layer of oil
• पानी का गिलास = glass of water
• सोने की अंगूठी = ring of gold / gold ring

It is a very common and natural Hindi structure.

Hindi usually does not have articles like English a, an, and the.

So परत can mean:

• a layer
• the layer

The exact meaning depends on context.

In this sentence, English will often use a layer of oil, but Hindi does not need a separate word for a.

The important genders here are:

• सतह = feminine
• परत = feminine
• तेल = masculine

Gender matters in Hindi because words like का / की / के and many adjectives and verbs may change according to gender and number.

In this sentence, the key visible agreement is:

• तेल की परत

It uses की because परत is feminine singular.

In the present tense, है is the singular form of is and does not show gender.

So whether the subject is masculine or feminine, you still use है for singular:

• किताब है = there is a book
• घर है = there is a house

If it were plural, you would use हैं:

• तेल की परतें हैं = there are layers of oil

So here है is singular because परत is singular.

The core noun being talked about is परत.

• तेल tells you what kind of layer it is
• सतह पर tells you where it is
• परत is the main thing that है refers to

So the sentence is really saying:

A layer is on this surface
more naturally, There is a layer of oil on this surface.

Yes, Hindi word order is somewhat flexible, but some orders are more natural than others.

The most neutral form is:

• इस सतह पर तेल की परत है।

You could also say:

• तेल की परत इस सतह पर है।

That puts more focus on तेल की परत.

Both are grammatical, but the original sentence sounds very natural and neutral.

You would make परत plural and change है to हैं.

Singular:

• इस सतह पर तेल की परत है।
• There is a layer of oil on this surface.

Plural:

• इस सतह पर तेल की परतें हैं।
• There are layers of oil on this surface.

Notice:

• परत → परतें
• है → हैं

सतह is usually pronounced roughly like sa-tah.

A simple learner-friendly guide:

• स = s
• त = dental t
• ह = h

So you can think of it as satah.

The final ह is pronounced, though in fast speech it may sound light.

Yes. It is a very natural expression for a layer/film of oil.

Hindi often uses X की परत for a layer of X:

• धूल की परत = layer of dust
• बर्फ की परत = layer of ice
• रंग की परत = layer/coat of paint

So this pattern is very useful to learn.