सुबह दूध ठंडा है।

Hindi usually prefers Subject–Object/Complement–Verb order, so the main verb often comes at the end.

In this sentence:

• सुबह = in the morning / morning
• दूध = milk
• ठंडा = cold
• है = is

So the structure is roughly:

• सुबह — time expression
• दूध — subject
• ठंडा — adjective/predicate
• है — linking verb

A very literal arrangement would be:

• In the morning, milk cold is.

That sounds strange in English, but it is normal in Hindi.

Here सुबह means in the morning or during the morning.

By itself, सुबह literally means morning, but Hindi often uses time words without adding an extra preposition-like word, especially when the meaning is clear.

So:

• सुबह दूध ठंडा है। = The milk is cold in the morning.

Depending on context, it can also feel like:

• Morning-time, the milk is cold.

Usually, with common time expressions, Hindi does not need में.

So सुबह, शाम, रात, आज, कल, etc. often appear by themselves:

• सुबह = in the morning
• शाम = in the evening
• रात = at night

That means सुबह दूध ठंडा है is perfectly natural.

You may sometimes hear सुबह में, but it is less common and often unnecessary in simple sentences like this. For a learner, it is safest to remember:

• सुबह alone is normal.

Because ठंडा agrees with दूध, and दूध is a masculine singular noun in Hindi.

Hindi adjectives often change form to match the gender and number of the noun they describe.

For this adjective:

• masculine singular: ठंडा
• feminine singular: ठंडी
• masculine plural: ठंडे

So:

• दूध ठंडा है। = The milk is cold.
• चाय ठंडी है। = The tea is cold.
  (चाय is feminine)

This is a very important pattern in Hindi.

Yes, दूध is treated as masculine in standard Hindi.

Unfortunately, grammatical gender in Hindi is often something you simply have to learn along with the noun. Sometimes there are patterns, but many nouns must be memorized.

You can often notice a noun’s gender by seeing what adjectives or verbs are used with it. In this sentence, ठंडा shows that दूध is masculine singular.

So this sentence is a useful reminder:

• दूध → masculine
• therefore ठंडा

है means is here.

It is the present-tense form of the verb होना (to be) for he/she/it/this/that and singular nouns.

So:

• दूध ठंडा है। = The milk is cold.

Without है, the sentence may sound incomplete in standard neutral Hindi.

A useful comparison:

• मैं खुश हूँ। = I am happy.
• वह खुश है। = He/she is happy.
• दूध ठंडा है। = The milk is cold.

So है is the linking verb connecting milk and cold.

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

So दूध can mean:

• milk
• the milk
• sometimes even some milk

The exact meaning depends on context.

In this sentence, English naturally translates it as the milk is cold in the morning or simply milk is cold in the morning, depending on the situation.

This is very normal in Hindi. You do not need to add a separate word for the.

Yes, time expressions in Hindi are fairly flexible.

These can all be possible, depending on emphasis and context:

• सुबह दूध ठंडा है।
• दूध सुबह ठंडा है।

The first one sounds like you are setting the time first: In the morning, the milk is cold.

The second one puts दूध first, so it feels a little more like: The milk is cold in the morning.

The basic meaning stays similar.

It is an adjective, but specifically it is being used as a predicate adjective.

That means it comes after the noun in meaning, not directly before it.

Compare:

• ठंडा दूध = cold milk
  (ठंडा directly describes दूध inside the noun phrase)

• दूध ठंडा है = the milk is cold
  (ठंडा is part of the statement about the milk)

In your sentence, ठंडा is not just labeling the milk; it is telling us the milk’s condition.

No, a Hindi speaker would understand it as a normal sentence meaning that the milk is cold in the morning.

The reason is that:

• दूध is the noun being talked about
• ठंडा है is a very common pattern meaning is cold
• सुबह is a time expression at the beginning

So the structure is clear to a Hindi speaker.

If you wanted cold milk as a noun phrase, you would normally say:

• ठंडा दूध

But here we have:

• दूध ठंडा है = milk is cold

That distinction is very useful in Hindi.

A simple pronunciation guide is:

• सुबह ≈ subah
• दूध ≈ doodh
• ठंडा ≈ thanda with a retroflex ṭh sound
• है ≈ hai

Very roughly:

• subah doodh thanda hai

A few notes:

• दूध has a long ū sound, like doo in doom
• ठ is not the same as English t; it is a retroflex sound made with the tongue curled back a bit
• है sounds like hai, rhyming roughly with eye, though shorter and lighter in connected speech

You would just replace the time word:

• रात दूध ठंडा है। = The milk is cold at night.

Or more naturally in many contexts:

• रात को दूध ठंडा है।

Time expressions in Hindi can vary a bit, so some are used plainly and some often take को.

For your original sentence, though, सुबह by itself is very natural:

• सुबह दूध ठंडा है।

This helps show that the main grammar of the sentence is:

• [time] + [noun] + [adjective] + है