Anotamos ese pensamiento.

Because Spanish often leaves out the subject pronoun when the verb ending already shows who is doing the action. The ending -amos tells you the subject is we.

So:

• Anotamos ese pensamiento. = We write down / wrote down that thought.
• Nosotros anotamos ese pensamiento. = also correct, but more emphatic, like we wrote it down.

Spanish does this much more often than English.

It can mean either one, depending on context.

Anotamos has the same form in:

• the present tense: we write down / we note
• the preterite: we wrote down / we noted

So only context tells you which one is meant.

Examples:

• Cada vez que aparece una idea, anotamos ese pensamiento.
  = present: we write down that thought
• Ayer anotamos ese pensamiento.
  = past: we wrote down that thought

This is very common with -ar verbs in the nosotros form.

Here, anotar means to write down, to note, or to make a note of something.

It is not just to write in a general sense. It usually suggests recording something briefly so you do not forget it.

So anotamos ese pensamiento has the idea of:

• we write that thought down
• we note that thought
• we make a note of that thought

Because ese pensamiento is a direct object, and it is a thing, not a person.

Spanish uses the personal a mainly with specific people, and sometimes pets or personified beings.

Compare:

• Vemos a María. = we see María
• Anotamos ese pensamiento. = we write down that thought

You do not say anotamos a ese pensamiento, because pensamiento is not a person here.

Ese is a demonstrative adjective meaning that.

In broad terms:

• este = this
• ese = that
• aquel = that over there / that one farther away

So ese pensamiento means that thought.

In real usage, ese often refers to something already mentioned, known, or a bit removed from the speaker. A learner should mainly remember:

• este pensamiento = this thought
• ese pensamiento = that thought

Because pensamiento is a masculine noun, so the demonstrative must agree with it.

Agreement in Spanish means matching:

• gender: masculine or feminine
• number: singular or plural

So:

• ese pensamiento = that thought
• esos pensamientos = those thoughts

If the noun were feminine, you would use esa:

• esa idea = that idea

Because ese already does the job of pointing out the noun. In Spanish, a demonstrative like este, ese, aquel normally replaces the article.

So you say:

• ese pensamiento = that thought

Not:

• el ese pensamiento ❌

This is similar to English: you say that thought, not the that thought.

Yes. Anotamos ese pensamiento is a normal, neutral word order:

• verb + object

But Spanish allows other orders for emphasis or style.

For example:

• Ese pensamiento lo anotamos.
  = That thought, we wrote it down.
• Ese pensamiento anotamos.
  = possible in some contexts, but less neutral

The basic version Anotamos ese pensamiento is the most straightforward one for learners.

Often they are very close, especially in everyday Spanish.

Both can mean to write down or to note something. In many situations, either works:

• Anotamos ese pensamiento.
• Apuntamos ese pensamiento.

That said, there can be slight differences in tone or usage:

• anotar often sounds a bit more neutral or formal
• apuntar is very common in everyday speech

Also, both verbs can have other meanings in different contexts, so context matters.

Because by normal Spanish stress rules, anotamos is stressed on the next-to-last syllable:

• a-no-TA-mos

Words ending in -n, -s, or a vowel usually have natural stress on the penultimate syllable, so no written accent is needed.

This is also why the present and preterite forms look identical here:

• anotamos = present we write down
• anotamos = preterite we wrote down

Same spelling, same stress, different meaning depending on context.

A simple pronunciation guide is:

• anotamos = ah-noh-TAH-mohs
• ese = EH-seh
• pensamiento = pen-sah-MYEN-toh

So the whole sentence is roughly:

ah-noh-TAH-mohs EH-seh pen-sah-MYEN-toh

In Spain, pronunciation may vary slightly by region, but this guide is a good standard approximation for learners.