اليوم أتكلم الإنجليزية في العمل.

Because the verb itself already shows the subject.

In أتكلم, the prefix أـ tells you the subject is I. So Arabic does not need a separate أنا here.

• أتكلم = I speak / I am speaking
• أنا أتكلم is also possible, but it adds emphasis, contrast, or extra clarity

So:

• اليوم أتكلم الإنجليزية في العمل. = neutral
• اليوم أنا أتكلم الإنجليزية في العمل. = more emphatic, like today, I am speaking English at work

أتكلم is a present-tense verb in the first person singular.

It comes from the verb تكلّم = to speak / to talk.

So:

• أتكلم = I speak
• It can also mean I am speaking, depending on context

In Modern Standard Arabic, the present tense often covers both:

• simple present: I speak
• present progressive: I am speaking

Context tells you which meaning is intended.

It can mean either one.

Arabic present tense is broader than English present tense. In English, you often have to choose between:

• I speak English at work
• I am speaking English at work today

In Arabic, أتكلم can cover both. The word اليوم = today makes the sentence sound more tied to the present situation, so many learners will naturally understand it as something like Today I’m speaking English at work.

Arabic allows flexible word order, especially with time expressions.

Putting اليوم at the beginning gives time emphasis:

• اليوم أتكلم الإنجليزية في العمل. = Today, I speak/am speaking English at work.

You could also say:

• أتكلم الإنجليزية في العمل اليوم.
• أتكلم الإنجليزية اليوم في العمل.

All are possible, but starting with اليوم highlights today.

Here, اليوم means today.

Literally, it is related to the day, but in normal usage it commonly functions as the adverb today.

So in this sentence it is not acting like a regular noun meaning the day. It is a time expression telling you when the action happens.

الإنجليزية is the feminine form, and that is very common when naming languages in Arabic.

A useful way to think about it is that there is an implied noun:

• اللغة الإنجليزية = the English language

Because اللغة is feminine, the adjective is feminine too:

• إنجليزي = English, masculine adjective
• إنجليزية = English, feminine adjective

When the word stands by itself to mean the language, Arabic often uses the feminine form:

• أتكلم العربية = I speak Arabic
• أدرس الفرنسية = I study French
• أفهم الإنجليزية = I understand English

So الإنجليزية here means the English language.

In Modern Standard Arabic, names of languages are very often used with the definite article الـ.

So Arabic commonly says:

• أتكلم العربية
• أدرس الفرنسية
• أفهم الإنجليزية

This is normal and idiomatic.

In this sentence, الإنجليزية is the direct object of أتكلم:

• أتكلم الإنجليزية = I speak English

You may also see the fuller expression:

• أتكلم اللغة الإنجليزية = I speak the English language

Yes, في basically means in, but Arabic often uses it where English uses at.

So:

• في العمل = literally in the work
• natural English meaning = at work

This is just a normal Arabic way to express location or setting.

Compare:

• في البيت = at home / in the house
• في المدرسة = at school
• في المكتب = in the office / at the office

So في العمل is the usual way to say at work.

Arabic uses the definite article in many places where English does not.

So في العمل is idiomatic Arabic for at work, even though the literal word-for-word meaning looks like in the work.

This does not mean a very specific piece of work in the English sense. It is simply the normal Arabic expression.

In fully vocalized Modern Standard Arabic, the sentence would be:

اليومَ أتكلمُ الإنجليزيةَ في العملِ

The endings are:

• اليومَ — accusative as an adverbial time expression
• أتكلمُ — nominative ending on the present-tense verb
• الإنجليزيةَ — accusative because it is the direct object
• العملِ — genitive because it comes after في

However, in everyday reading, writing, and much spoken MSA, these short vowel endings are usually not written or fully pronounced. So learners often see:

اليوم أتكلم الإنجليزية في العمل

Yes, you can.

Both are grammatical:

• اليوم أتكلم الإنجليزية في العمل.
• اليوم أنا أتكلم الإنجليزية في العمل.

The version without أنا is more neutral because the verb already tells you the subject.

The version with أنا gives extra emphasis, for example:

• to stress I
• to contrast with someone else
• to make the sentence sound more explicit

Yes, to a degree.

Arabic word order is more flexible than English, especially with time and place phrases. For example:

• اليوم أتكلم الإنجليزية في العمل.
• أتكلم الإنجليزية في العمل اليوم.
• في العمل أتكلم الإنجليزية اليوم.

These all express roughly the same basic idea, but the focus changes slightly.

A simple guide:

• put اليوم first if you want to emphasize today
• put في العمل first if you want to emphasize at work
• keep أتكلم الإنجليزية together if you want the core action to feel central

Yes, in many contexts it would.

Both verbs can mean to speak / to talk:

• أتكلم الإنجليزية = I speak English
• أتحدث الإنجليزية = I speak English

For many learners, أتكلم feels a little more straightforward in sentences about languages, while أتحدث is also very common and perfectly correct.

So this sentence could also be:

اليوم أتحدث الإنجليزية في العمل.

That said, since your sentence already uses أتكلم, that is an excellent and natural choice.