اللاعب بالملعب.

A common Levantine pronunciation is il-lāʿeb bil-malʿab.

A few notes:

• اللاعب sounds like il-lāʿeb
• بالملعب sounds like bil-malʿab
• The sound ع in both words is the deep throat sound ʿ

In very fast speech, the initial vowel in il- may get weaker, but il-lāʿeb bil-malʿab is a good learner-friendly pronunciation.

Because Arabic often leaves out the present-tense to be.

So Arabic says something like:

the player in the stadium

but the meaning in natural English is:

The player is in the stadium.

This is very normal in both Levantine and Standard Arabic for present-time sentences.

It can be understood as a complete sentence: The player is in the stadium / on the field.

But depending on context, it could also function like a phrase, such as:

the player in the stadium

For a beginner, the most useful reading is usually the full sentence meaning.

Here, بـ means in or at.

So:

• الملعب = the field / the stadium
• بالملعب = in the field / at the stadium / on the field

In Levantine, بـ is very commonly used for location.

Because both nouns are definite.

• اللاعب = the player
• الملعب = the field / the stadium

When بـ comes before الملعب, they combine into بالملعب.

So بالملعب is basically:

بـ + الملعب

meaning in the stadium or on the field.

Because ل is a sun letter.

In Arabic, when ال comes before a sun letter, the l of the article blends into the first consonant of the noun. So اللاعب is pronounced with a doubled l sound:

il-lāʿeb

not a fully separated il alāʿeb-type pronunciation.

You may sometimes see it written more clearly with a shadda as اللّاعب.

Yes. They both come from the same root: ل-ع-ب, which has to do with playing.

• لاعب = player
• ملعب = place of playing → field, court, playground, stadium

This is a very useful pattern in Arabic:

• a person doing the action
• a place where the action happens

It can mean any of those, depending on context.

ملعب can refer to:

• a field
• a court
• a playground
• a stadium or sports ground

So بالملعب could be understood as:

• on the field
• in the stadium
• at the sports ground

The exact translation depends on what sport or situation you are talking about.

Yes, it is understandable and natural.

A Levantine speaker can definitely say:

اللاعب بالملعب

If they want to stress that the player is physically inside the place, they might also say:

اللّاعب جوّا الملعب

which means The player is inside the field/stadium.

So your sentence is fine, and there are also slightly more specific everyday alternatives.

For the negative, a common Levantine version is:

اللّاعب مو بالملعب
= The player is not in the stadium / on the field

For a yes-no question, you can often just use the same words with rising intonation:

اللّاعب بالملعب؟
= Is the player in the stadium?

In everyday Levantine, intonation is usually enough. Formal هل is much more Standard Arabic than everyday spoken Levantine.