Rådyret går roligt mellem træerne om morgenen.

Because rådyr is a neuter noun: et rådyr = a roe deer. In Danish, the definite article is usually added to the end of the noun instead of being a separate word.

• et rådyr = a roe deer
• rådyret = the roe deer

So the ending -et here is the definite singular ending.

It can be a little confusing because rådyr is often the same in singular and plural in its indefinite form.

• et rådyr = a roe deer
• flere rådyr = several roe deer

But in this sentence, rådyret is definitely singular because of the ending -et, which means the roe deer.

It can mean both, depending on context. Danish present tense often covers both simple present and present continuous.

So rådyret går roligt... can mean:

• The roe deer walks calmly...
• The roe deer is walking calmly...

The exact English choice depends on the situation, but the Danish form stays the same: går.

Gå is the infinitive, meaning to walk or to go.
Går is the present tense form.

• at gå = to walk / to go
• går = walks / is walking

Danish present tense is usually formed by adding -r to the infinitive.

Because roligt is being used adverbially. The basic adjective is rolig, meaning calm or quiet. When Danish uses many adjectives as adverbs, it often uses the -t form.

• en rolig morgen = a calm morning
• går roligt = walks calmly

So roligt here means something like calmly, quietly, or gently.

It suggests calm, unhurried, peaceful movement. In English, depending on context, you might translate it as:

• calmly
• quietly
• gently

It does not necessarily mean the deer is making no sound at all. It mainly describes the manner of movement as relaxed and peaceful.

Mellem literally means between, but in natural English this sentence may also be understood as among, depending on the picture or context.

• mellem træerne = between the trees
• in smoother English, sometimes among the trees

Danish often uses mellem in places where English might choose either between or among.

Træerne already includes the meaning the trees.

Here is the pattern:

• et træ = a tree
• træer = trees
• træerne = the trees

So:

• -er marks the plural
• -ne marks the definite plural

That is why Danish does not need a separate word like English the here. The definiteness is built into træerne itself.

This is a very normal Danish sentence order:

• Rådyret = subject
• går = verb
• roligt = manner
• mellem træerne = place
• om morgenen = time

So the structure is basically:

subject + verb + manner + place + time

That is not the only possible order in Danish, but it is a very standard and natural one.

Om morgenen is an idiomatic time expression meaning in the morning.

• om morgenen = in the morning
• i morgen = tomorrow

So these are completely different:

• Rådyret går roligt mellem træerne om morgenen. = The roe deer walks calmly between the trees in the morning.
• ... i morgen would mean ... tomorrow

Also note that morgenen is definite here. Danish often uses this pattern with parts of the day:

• om morgenen = in the morning
• om aftenen = in the evening
• om natten = at night / in the night

It can mean either, depending on context.

• It can set the scene: in the morning
• It can describe a habit: in the mornings

If you specifically want this morning, Danish often uses i morges instead.

So without more context, om morgenen is a more general expression.

A few sounds here are especially hard for English speakers:

• å in rå- sounds roughly like a long o sound, though not exactly like English.
• y in dyr has no exact English equivalent. A good trick is to say ee while rounding your lips.
• æ in træ is somewhat like the a in cat, but usually more open.
• Danish r is not like a strong English r, and final -r can be quite weak.

Very rough guides:

• rådyret ≈ ROH-dy-ret
• træerne ≈ TREH-er-ne
• morgenen ≈ MOR-ge-nen

These are only approximations. For pronunciation, listening to native audio is much more reliable than English spelling.