Lupa este pe tarabă.

Because lupa is the definite form of the noun.

The basic noun is lupă = magnifying glass.
Romanian usually adds the definite article to the end of the noun:

• lupă = a magnifying glass
• lupa = the magnifying glass

So the final -ă changes to -a when the feminine singular definite article is added.

Romanian usually puts the definite article at the end of the noun, not as a separate word before it.

So instead of something like English the magnifying glass, Romanian says:

• lupă = a magnifying glass
• lupa = the magnifying glass

This is one of the first big differences English speakers notice in Romanian.

Lupă is a feminine noun.

You can tell from its forms:

• o lupă = a magnifying glass
• două lupe = two magnifying glasses
• lupa = the magnifying glass

That pattern is typical of many feminine nouns in Romanian.

Este means is.

Yes, in everyday Romanian, people very often use e instead of este:

• Lupa este pe tarabă.
• Lupa e pe tarabă.

Both are correct.
Este sounds a little fuller or more careful; e is very common in normal speech.

Here, pe means on.

So pe tarabă means on the stall / on the stand / on the market table, depending on context.

Important: Romanian pe can also have other uses, including marking certain direct objects, but in this sentence it is simply a preposition of place.

Tarabă usually means a market stall, vendor’s stand, or display counter/table in a market setting.

So the sentence gives a picture of the magnifying glass being located on some kind of selling surface or stall.

Depending on context, English translations can vary a little:

• stall
• stand
• counter
• sometimes table in a market sense

Pe tarabă uses the indefinite form: tarabă = a stall / stall.

If you say pe taraba, that is the definite form: on the stall.

So the contrast is:

• pe tarabă = on a stall / on stall / on the market stall area in a more general sense
• pe taraba = on the specific stall

In real Romanian, pe tarabă can sound quite natural even when English might prefer on the stall, especially in market-related contexts.

A simple English-friendly approximation is:

LOO-pa YES-te pe ta-RA-buh

A few notes:

• lu in Lupa sounds like loo
• este is roughly YES-te
• pe is like peh
• tarabă has stress on ra: ta-RA-bă
• the final ă is a short, neutral vowel, something like the a in sofa

Romanian pronunciation is generally fairly regular, so once you learn the sounds, it becomes predictable.

The Romanian ă is a very common vowel. It sounds like a short, unstressed uh or the a in English sofa.

So:

• tarabă ≈ ta-RA-buh
• the last sound is ă, not a strong a like in father

This vowel appears constantly in Romanian, so it is worth getting used to early.

The neutral, most straightforward order is:

Lupa este pe tarabă.
Subject + verb + place

That is the normal beginner-friendly pattern.

Romanian word order is somewhat flexible, though, especially for emphasis. For example, you might hear:

• Pe tarabă este lupa.

But that sounds more marked or contrastive, something like The magnifying glass is on the stall with extra focus on the location.

So for everyday use, the original order is the safest one.

In standard Romanian, you normally keep the verb:

• Lupa este pe tarabă.
• Lupa e pe tarabă.

Romanian usually does not drop is in this kind of sentence the way Russian or some other languages can.

So for a full sentence, use este or e.

Yes. It is a complete and grammatically normal sentence.

It has:

• a subject: Lupa
• a verb: este
• a place expression: pe tarabă

It sounds like a simple textbook sentence, but it is fully correct Romanian.