La vasija está en el torno.

Because this sentence is talking about location: the vessel is on/in the wheel. In Spanish, location is normally expressed with estar, not ser.

• La vasija está en el torno = the vessel is on the wheel
• Ser is usually for identity, origin, material, time, etc.

So for where something is, estar is the natural choice.

Vasija is a fairly general word meaning vessel, container, or sometimes pot. It often sounds a bit more formal or general than very everyday words like vaso or olla.

Depending on context, vasija could refer to:

• a ceramic vessel
• a container
• a pot-shaped object

In a pottery context, it fits very well.

Here, torno means a potter’s wheel.

The word torno can also mean other kinds of lathe or turning machine, so the exact meaning depends on context. Because the sentence mentions la vasija, the most natural interpretation is pottery: the vessel is on the potter’s wheel.

This is a very common kind of difference between English and Spanish. Spanish often uses en where English uses on, in, or even something else.

So:

• on the wheel in English
• en el torno in Spanish

You should learn en here as the normal Spanish preposition with this expression, rather than trying to match it word-for-word with English.

The accent mark shows where the stress goes: es-TÁ.

It also helps distinguish this verb form from esta, which can be a demonstrative word in older spelling traditions or appear in other contexts without being the verb. In modern practical learning, the main point is:

• está = is
• the accent is required

Because vasija is a feminine noun and torno is a masculine noun.

So their articles are:

• la vasija
• el torno

This is grammatical gender, which is a normal part of Spanish nouns. The article has to agree with the noun:

• feminine singular: la
• masculine singular: el

Yes, in this sentence the article is normally needed.

Spanish often uses the definite article where English may or may not use one. Here, en el torno means on the wheel or in the wheel, referring to the relevant wheel in the situation.

Saying just en torno would not mean the same thing. In fact, en torno a is a completely different expression meaning something like around or regarding.

The normal, neutral order is:

La vasija está en el torno.

That is the most natural way to say it in most situations.

But Spanish can change word order for emphasis, for example:

• En el torno está la vasija.

That sounds more marked or literary, and it puts more focus on where the vessel is. For everyday use, stick with La vasija está en el torno.

In Spain, vasija is pronounced roughly like:

ba-SEE-ha

A few helpful points:

• v and b sound very similar in Spanish
• the stress falls on si: va-SI-ja
• the j sounds like a strong throaty h sound in English, but harsher

So vasija does not sound like English vase.

Yes, but it depends on what object you mean.

Possible alternatives:

• la pieza = the piece
• el jarrón = the vase
• la olla = the pot
• el cuenco = the bowl

Vasija is useful because it is broad and works well for a pottery object whose exact type is not important.

Está is the third-person singular present tense of estar.

So it means:

• he/she/it is
• you are if using usted

In this sentence, it refers to la vasija, so the meaning is it is.

Yes, it sounds natural, especially in a pottery or workshop context.

A speaker in Spain would understand it as something like:

• the vessel is on the potter’s wheel
• the ceramic piece is on the wheel

If the context is clearly pottery, the sentence works well and sounds normal.