لما المكالمة خلصت، كنت قاعد بشرب عصير وهي كانت قاعدة بتحط الملح في الصلصة.

In Egyptian Arabic, لما often means when.

So لما المكالمة خلصت means when the phone call ended.

It introduces a time clause, just like when in English:

• لما وصلت = when I arrived
• لما شافته = when she saw him

In this sentence, it sets the background for what was happening after the call ended.

المكالمة means the call / the phone call. The prefix الـ is the definite article, like the in English.

So:

• مكالمة = a call
• المكالمة = the call

Here, the speaker is referring to a specific call, so the call is natural.

خلصت comes from the verb خلص and here it means finished or ended.

So:

• المكالمة خلصت = the call ended / the call finished

In Egyptian Arabic, خلص is very common and can be used in several related ways:

• خلصت الشغل = I finished the work
• الشغل خلص = the work is finished
• خلص بقى = enough / stop it already

Here it is in the past tense, with المكالمة as the subject.

Because المكالمة is grammatically feminine.

In Arabic, verbs often agree with the subject in gender. Since مكالمة is feminine, the past tense verb appears in the feminine form:

• المكالمة خلصت = the call ended
• compare with a masculine noun: الفيلم خلص = the movie ended

Even though a call is not biologically female, Arabic nouns still have grammatical gender.

كنت قاعد بشرب gives an ongoing, background action in the past. It is similar to I was sitting drinking juice or more naturally I was drinking juice.

This pattern is very common in Egyptian Arabic:

• كان/كنت + قاعد/قاعدة + بـ + verb

It often emphasizes that the action was in progress at that time.

Compare:

• شربت عصير = I drank juice / I had juice
  This sounds like a completed action.
• كنت بشرب عصير = I was drinking juice
• كنت قاعد بشرب عصير = I was sitting there drinking juice

So قاعد adds a sense of being in that state or position while the action was happening.

Originally, yes: قاعد literally means sitting.

But in Egyptian Arabic, قاعد and قاعدة are also often used more loosely in continuous-action expressions. They do not always strongly emphasize the physical posture. Very often they just help express that someone is in the middle of doing something.

So:

• كنت قاعد بشرب عصير can literally suggest I was sitting drinking juice
• but in normal usage it may simply mean I was drinking juice

Likewise:

• كانت قاعدة بتحط الملح = she was putting the salt
• not necessarily emphasizing that she was physically seated

It is a very natural colloquial way to express an ongoing action.

In Egyptian Arabic, the prefix بـ on the present verb is very common. It is used for:

• habitual actions
• present actions
• ongoing actions, especially in context

Here, because the verbs are inside a past continuous frame with كنت and كانت, they express actions that were in progress:

• بشرب = I drink / I am drinking
• بتحط = she puts / she is putting

With كنت or كانت, the meaning becomes:

• كنت بشرب = I was drinking
• كانت بتحط = she was putting

So the بـ is a normal part of colloquial Egyptian present-tense-style verb forms.

Sometimes one can be enough, depending on style.

For example:

• كنت بشرب عصير = I was drinking juice
• كنت قاعد بشرب عصير = I was sitting / I was there drinking juice

The version with قاعد is a little more vivid and colloquial. It paints the scene more clearly.

So:

• كنت gives the past frame: was
• قاعد adds the sense of being in the middle of the situation
• بشرب gives the actual action

This layering is very natural in spoken Egyptian Arabic.

Because the subject is هي = she.

So everything agrees with a feminine singular subject:

• كانت = she was
• قاعدة = feminine form of قاعد
• بتحط = she puts / she is putting

Compare:

• هو كان قاعد بيحط الملح = he was putting the salt
• هي كانت قاعدة بتحط الملح = she was putting the salt

This kind of gender agreement is very important in Arabic.

بتحط is the Egyptian Arabic colloquial form of she puts / she is putting, from the verb حط = to put.

So:

• حط = put! or the root verb in colloquial usage
• بتحط = she puts / she is putting

The form تضع is Modern Standard Arabic, not normal everyday Egyptian speech.

A learner should notice this difference:

• Egyptian colloquial: بتحط الملح
• MSA: تضع الملح

Since your sentence is Egyptian Arabic, بتحط is exactly what you would expect.

و means and, and هي means she.

So وهي كانت قاعدة بتحط الملح في الصلصة means: and she was putting the salt in the sauce

In English, you might sometimes leave out the subject if it is clear, but Arabic often keeps it. Using هي makes the sentence clearer and nicely balances the two parts:

• كنت قاعد بشرب عصير
• وهي كانت قاعدة بتحط الملح في الصلصة

It helps show that two different people were doing two different ongoing actions.

Here في means in.

So:

• الملح = the salt
• في الصلصة = in the sauce

Together:

• بتحط الملح في الصلصة = she is putting the salt in the sauce

في is one of the most common prepositions in Arabic and often corresponds to in, inside, or sometimes at, depending on context.

Because in this context the speaker is referring to specific salt and a specific sauce.

• الملح = the salt
• الصلصة = the sauce

In natural speech, Arabic often uses the definite article where English might also use the, especially when the items are understood from the situation.

For example, if someone is cooking, the salt and the sauce are naturally identifiable from context.

The word order is very natural for Egyptian Arabic.

The sentence is structured like this:

• لما المكالمة خلصت
• كنت قاعد بشرب عصير
• وهي كانت قاعدة بتحط الملح في الصلصة

This is basically:

• When the call ended,
• I was drinking juice,
• and she was putting salt in the sauce.

Arabic word order is flexible, but this version sounds smooth and conversational. It first gives the time setting, then describes the two simultaneous background actions.

Yes, absolutely.

You could say:

• لما المكالمة خلصت، كنت بشرب عصير وهي كانت بتحط الملح في الصلصة or even:
• لما المكالمة خلصت، كنت بشرب عصير وهي بتحط الملح في الصلصة

That would still be understandable and natural.

Adding قاعد/قاعدة makes the scene feel a bit more vivid, colloquial, and ongoing. It is not always strictly necessary, but it is very common in Egyptian speech.

The sentence combines:

1. a short completed past event
2. two ongoing past actions

So:

1. لما المكالمة خلصت
   = when the call ended
   This is a completed event in the past.

2. كنت قاعد بشرب عصير
   = I was drinking juice

3. وهي كانت قاعدة بتحط الملح في الصلصة
   = and she was putting salt in the sauce

This is very similar to English:

• When X happened, I was doing Y, and she was doing Z.

So the sentence is a good example of how Egyptian Arabic expresses background actions that were already in progress when another event happened.