قصر الكم بالمقص.

A common Egyptian pronunciation would be roughly ʔaṣṣar el-komm bel-maʔaṣṣ.

A few useful notes:

• ق is often pronounced as a glottal stop ʔ in Egyptian Arabic.
• الكم is pronounced el-komm.
• بالمقص is pronounced bel-maʔaṣṣ.
• The spelling does not show the short vowels, so you may see slightly different transliterations.

Here, قصر is the verb قصّر, meaning to shorten or make shorter.

It is not the noun قصر meaning palace. Arabic script often leaves out short vowels and other marks, so different words can look identical in writing.

So in this sentence, the intended reading is the verb قصّر = shortened.

Because Arabic verbs often include the subject inside the verb itself.

Here, قصر can be understood as he shortened if the sentence is being read as past tense. Arabic does not need a separate word for he unless you want emphasis.

So:

• قصر الكم بالمقص = He shortened the sleeve with the scissors
• هو قصر الكم بالمقص = also possible, but هو is usually unnecessary

Yes. In unvowelled Arabic writing, this form can be ambiguous.

Depending on context, قصر الكم بالمقص could be understood as:

• He shortened the sleeve with the scissors
• or Shorten the sleeve with the scissors

This is very common in Arabic: the script leaves out short vowels, so context tells you which reading is meant.

Here, الكم means the sleeve.

It is a different word from كم meaning how much/how many. They look similar in plain writing, but they are different words.

In this sentence:

• الـ = the
• كم = sleeve

So الكم = the sleeve.

The بـ here means with or by means of. It marks the instrument used to do the action.

So:

• بالمقص = with the scissors

Also, بـ combines with الـ:

• بـ + الـ = بال

That is why you see بالمقص rather than writing the two separately.

Because Arabic and English do not always package objects the same way.

In Arabic, مقص is commonly treated as a single tool name, even though in English we normally say scissors.

So the grammar is normal in Arabic:

• بالمقص = with the scissors

This is similar to how different languages sometimes use singular where English uses plural, or vice versa.

Because normal Arabic writing usually leaves out most diacritics.

That means the sentence is written in a simplified everyday way. A fuller learner-friendly version might show marks like this:

• قصّر الكم بالمقص

Those marks help show:

• the short vowels
• the doubled consonants, such as in قصّر
• the correct reading of the words

Native readers usually rely on context, not full vowel marks.

Because قصّر means to shorten, while قصّ means to cut in a more general sense.

So the difference is roughly:

• قصّ = cut
• قصّر = shorten / make shorter

If the idea is that the sleeve became shorter, قصّر is the more precise choice.

The order is:

• قصر = verb
• الكم = direct object
• بالمقص = prepositional phrase showing the instrument

So the structure is:

verb + object + instrument

This is a very normal Arabic sentence pattern, especially when the sentence begins with a past-tense verb.