Learn Hardcore Portuguese (Portugal): O diário ajuda-me a organizar os pensamentos do dia passado. - The diary helps me organise the thoughts from the past day.

In European Portuguese, unstressed object pronouns (me, te, se, nos, vos, etc.) usually come after the verb in affirmative main clauses when nothing forces them to come before. This is called enclisis.

So:

O diário ajuda-me. – correct (EP)
O diário me ajuda. – sounds Brazilian, not standard European.

If there is something that attracts the pronoun to the front (negation, some adverbs, some conjunctions, etc.), then it goes before the verb:

O diário não me ajuda. – The diary doesn’t help me.
Quando escrevo, isso me ajuda. (BP) vs Quando escrevo, isso ajuda-me. (EP – but proclisis is also possible here depending on style)

In your sentence, there is no such “attractor”, so ajuda-me is the normal European Portuguese order.

What is the purpose of the hyphen in ajuda-me?

The hyphen shows that me is a clitic pronoun and is attached to the verb ajudar.

Writing:

ajuda me (without hyphen) is wrong.
ajuda-me (with hyphen) is correct.

Whenever these unstressed pronouns come after the verb in European Portuguese (enclisis or mesoclisis), they are joined to the verb with a hyphen:

ajuda-me – help me
dá-me – give me
disseram-me – they told me

If there are two pronouns, both follow the verb and are chained with hyphens:

dá-mo – give it to me (dá + me + o)

Can I say O diário me ajuda instead of O diário ajuda-me?

That word order (O diário me ajuda) is typical of Brazilian Portuguese.

In European Portuguese, the natural and standard form in a neutral affirmative sentence is:

O diário ajuda-me.

Using O diário me ajuda in Portugal will usually sound Brazilian or non‑native. People will understand you, but it’s not the standard pattern they expect.

So, for European Portuguese, keep:

ajuda-me (verb + hyphen + pronoun) in affirmative statements, unless something pulls the pronoun to the front (negation, etc.).

Why do we say ajuda-me a organizar and not just ajuda-me organizar or ajuda-me para organizar?

In Portuguese, ajudar normally follows the structure:

ajudar alguém a fazer alguma coisa
(to help someone to do something)

So you need the preposition a before the infinitive:

O diário ajuda-me a organizar os pensamentos.
The diary helps me to organize my thoughts.

Without a, ajuda-me organizar sounds wrong in standard Portuguese.

Using para changes the meaning and also sounds off here:

ajudar para organizar would suggest something like “help in order to organize / help so that it organizes”, which is not the usual complementation pattern of ajudar.

So the correct, natural pattern is:

ajuda-me a organizar.

Why is it os pensamentos and not just pensamentos, when in English we say “thoughts” without “the”?

Portuguese uses the definite article (o, a, os, as) much more often than English, especially when we are referring to a specific, identifiable set of things.

Here, os pensamentos do dia passado refers to the particular thoughts from that past day, not thoughts in general. That’s why the article is used:

organizar os pensamentos do dia passado
≈ organize the (specific) thoughts from the previous day

If you said just organizar pensamentos, it would sound more like “to organize thoughts (in general)”, not those specific ones.

So the article os signals that we’re talking about a defined set of thoughts, which matches the idea in the English sentence even though English doesn’t show it with “the”.

What exactly does do mean in do dia passado?

do is a contraction of the preposition de + the masculine singular article o:

de + o = do

So literally:

os pensamentos do dia passado
= os pensamentos de o dia passado
= the thoughts of the past day / the thoughts from the previous day

Other similar contractions:

de + a = da → da semana passada (from last week)
de + os = dos → dos amigos (of/from the friends)
de + as = das → das pessoas (of/from the people)

Is dia passado the same as ontem? When would I use each?

They are related but not identical.

ontem is an adverb meaning yesterday (a point in time).
dia passado is a noun phrase: the past day / the previous day.

In os pensamentos do dia passado, the focus is on the day as a noun that “owns” the thoughts.

More natural everyday phrasing in Portuguese would probably be:

os pensamentos de ontem – yesterday’s thoughts
os pensamentos do dia anterior – the thoughts of the previous day

do dia passado is understandable and correct, but it can sound a bit more literary or formal than what people usually say in casual speech.

Could I say os pensamentos de ontem instead of os pensamentos do dia passado?

Yes, and in normal speech os pensamentos de ontem is more common and sounds more natural:

O diário ajuda-me a organizar os pensamentos de ontem.

This is very clear and idiomatic: The diary helps me organize yesterday’s thoughts.

os pensamentos do dia passado is fine, but:

sounds more formal or stylized;
is slightly less common in everyday conversation.

Both are grammatically acceptable, but de ontem is the safer, more natural choice for most contexts.

Why is passado after dia and not before it?

In Portuguese, adjectives usually come after the noun:

dia passado – literally day past
casa grande – big house
livro interessante – interesting book

So dia passado follows the regular pattern.

You generally wouldn’t say passado dia in this sense. The only time you might see passado before dia is in a set expression like:

no passado dia 15 de março – on last March 15th (formal, often in news/legal language)

But for your sentence, the normal option is do dia passado (or more naturally: de ontem or do dia anterior).

What does diário mean here? Is it a diary, a journal, or a newspaper?

diário can mean several things in Portuguese, depending on context:

personal diary / journal – where you write your thoughts and experiences.
newspaper – a daily paper (e.g. um diário regional).
daily as an adjective – something that happens every day (rotina diária – daily routine).

In your sentence:

O diário ajuda-me a organizar os pensamentos do dia passado.

The most natural interpretation is a personal diary or journal, because it “helps organize thoughts”. A newspaper would not normally be described in that way.

Why is the present tense ajuda used if we’re talking about the past day?

Portuguese (like English) uses the present tense to describe habitual or regular actions:

O diário ajuda-me a organizar os pensamentos do dia passado.
= The diary helps me (regularly) to organize the thoughts from the previous day.

So the time reference of the action (writing about the past day) is past, but the habit (“the diary helps me”) is something that happens now, repeatedly:

Every day, today’s diary helps you with yesterday’s thoughts.
That ongoing habit is expressed with the present tense ajuda.

Why is it me and not mim in ajuda-me?

Portuguese has two different forms:

me – unstressed clitic pronoun, attaches to the verb.
mim – stressed prepositional pronoun, used after prepositions.

You use:

me with verbs:
- ajuda-me – help me
- vê-me – see me
- disseram-me – they told me
mim after prepositions like para, de, por, sem, em:
- para mim – for me
- de mim – of me / from me
- sem mim – without me

So in ajuda-me, we need the form that attaches to a verb, which is me, not mim.