Este cuadro es igual al que vimos en el museo.

Yes. Cuadro is a flexible word in Spanish. In this sentence, it means painting or picture.

Depending on context, cuadro can also mean:

• a frame
• a chart or table
• a scene in a play
• even a situation in some expressions

Here, because of vimos en el museo (we saw in the museum), the most natural meaning is painting.

Spanish has three common demonstratives:

• este = this (near me)
• ese = that (near you / not so near me)
• aquel = that over there (far from both)

So este cuadro means this painting, something the speaker feels is close or present in the conversation.

All three are possible in other situations:

• Este cuadro = this painting
• Ese cuadro = that painting
• Aquel cuadro = that painting over there

The sentence uses the pattern igual a to mean the same as or similar to:

• igual a + noun / pronoun
• igual al que vimos = the same as the one we saw

Here, a + el becomes al, so igual a el que changes to igual al que.

You may also hear igual que in Spanish, and it is very common, especially in comparisons. But in this sentence, the structure chosen is igual a.

So:

• Este cuadro es igual al que vimos... = correct
• Este cuadro es igual que el que vimos... = also possible in many contexts, but this sentence is built with igual a

Al is a contraction of a + el.

Spanish always contracts a el to al (except when El is part of a proper name, like a El Escorial).

So:

• igual a el que vimos → igual al que vimos

This is not optional. If you have a + el, you normally must write al.

El que here means the one that or the one which.

It avoids repeating cuadro:

• Este cuadro es igual al cuadro que vimos en el museo.
• Este cuadro es igual al que vimos en el museo.

Both are correct, but the second sounds more natural because Spanish often avoids repeating the noun when it is obvious.

So:

• el que vimos = the one that we saw

Because the sentence refers to a specific masculine singular thing: cuadro.

• el que = the one that
• lo que = what / that which

Use el que when there is a specific noun behind it:

• el cuadro → el que

Use lo que when there is no specific noun, and the idea is more general:

• No entiendo lo que dices. = I don’t understand what you’re saying.

So in this sentence, lo que would be wrong because we are talking about a specific painting.

Vimos is the preterite of ver (to see), and it presents the action as a completed event:

• vimos = we saw

That fits well here because the speaker is referring to a finished visit or a specific moment in the past.

Compare:

• vimos = we saw it, completed event
• veíamos = we were seeing / used to see, more ongoing or background
• hemos visto = we have seen, also possible in some contexts, especially depending on region and how connected the past is to the present

In Spain, hemos visto is often common for recent past, but vimos is still perfectly normal when talking about a completed event.

The ending -imos already tells you the subject is nosotros / nosotras (we).

So Spanish often leaves out subject pronouns when they are clear from the verb form.

• vimos = we saw
• nosotros vimos = we saw

Both are correct, but Spanish usually prefers the version without the pronoun unless there is emphasis or contrast.

Yes, that is grammatically correct.

But it sounds more repetitive. Native speakers usually prefer:

• Este cuadro es igual al que vimos en el museo.

Using el que is a natural way to say the one that and avoid repeating cuadro.

So:

• igual al cuadro que vimos = correct, but heavier
• igual al que vimos = more natural

Yes, and that changes the meaning a little.

• es igual al que vimos = it is the same as / identical to / very similar to the one we saw
• es el mismo que vimos = it is the exact same one we saw

So el mismo is stronger. It usually means it is literally the very same painting, not just one that looks the same.

If you mean true identity, el mismo is often the better choice.

It is a relative clause. It describes el in el que.

So:

• el que = the one
• que vimos en el museo = that we saw in the museum

Together:

• el que vimos en el museo = the one that we saw in the museum

This whole part tells us which one the speaker is comparing the painting to.