ברגע שתא המדידה יהיה פנוי, אמדוד את הבגד.

ברגע ש־ literally means at the moment that, but in natural English it usually means as soon as, once, or simply when.

In this sentence, it introduces a time clause:

• ברגע שתא המדידה יהיה פנוי = As soon as the fitting room is available

It often suggests that one action will happen immediately after the other condition is met.

The ש־ here is a very short attached word meaning that / when in this kind of expression. In writing, it normally joins directly to the next word.

So:

• ש־ + תא → שתא

It is not שהתא, because the next word is תא, not התא.

A useful point: תא המדידה is definite even though תא itself does not have ה־ on it, because it is a construct phrase. So the clause begins with תא, and that is why you get שתא.

תא המדידה means the fitting room or the changing room.

Grammatically, it is a construct chain:

• תא = booth, cubicle, compartment
• מדידה = measuring / trying on

So literally it is something like:

• the measuring booth
• or more naturally, the fitting room

Why no ה־ on תא? Because in Hebrew construct phrases, definiteness can come from the second noun:

• תא מדידה = a fitting room
• תא המדידה = the fitting room

Even though only המדידה has ה־, the whole phrase becomes definite.

יהיה is the 3rd person masculine singular future form of להיות (to be).

It agrees with תא, which is a masculine singular noun:

• תא = masculine singular
• therefore: יהיה פנוי = will be available/free

So the grammar is:

• תא המדידה יהיה פנוי = the fitting room will be available

פנוי means free, available, vacant, or unoccupied, depending on context.

Here it means that the fitting room is not being used:

• יהיה פנוי = will be free / available

It is in the masculine singular form because it agrees with תא:

• masculine singular noun: תא
• masculine singular adjective: פנוי

If the noun were feminine, the adjective form would change.

This is very normal in Hebrew.

In English, we often say:

• As soon as the fitting room is free, I’ll try on the garment

English uses present tense in the time clause (is free) and future in the main clause (I’ll try on).

Hebrew commonly uses future tense in both clauses when both actions are in the future:

• ברגע שתא המדידה יהיה פנוי, אמדוד את הבגד.

So Hebrew is not copying English tense usage here. This is standard Hebrew structure.

אמדוד is the 1st person singular future of למדוד.

The basic meaning of למדוד is to measure, but with clothes it very often means to try on.

So:

• אמדוד את הבגד can literally be I will measure the garment
• but in a clothing-store context, especially with תא המדידה, it naturally means I will try on the garment

That is a common feature of this verb in Hebrew.

את is the marker of a definite direct object.

It does not have a direct English translation. It appears before a direct object that is definite, such as one with ה־.

Here:

• הבגד = the garment / the item of clothing
• because it is definite, Hebrew uses את
• so: אמדוד את הבגד

A very important point for English speakers: when למדוד means to try on, Hebrew still uses a direct object. English says try on the garment, but Hebrew does not need a separate word corresponding to on here.

Yes, הבגד is singular, and it means the garment, the item of clothing, or the piece of clothing.

This suggests one specific item.

If you wanted plural, you could say:

• אמדוד את הבגדים = I’ll try on the clothes / the garments

So the singular here is perfectly natural if the speaker is talking about one specific item.

Yes. Hebrew allows some flexibility.

The sentence as written begins with the time clause:

• ברגע שתא המדידה יהיה פנוי, אמדוד את הבגד.

You could also say:

• אמדוד את הבגד ברגע שתא המדידה יהיה פנוי.

Both are grammatical. The difference is mostly one of emphasis and flow:

• starting with ברגע... puts the timing first
• starting with אמדוד... puts the action first

The original version is very natural, especially if the speaker wants to emphasize waiting until the fitting room is available.