Learn Hardcore Czech: Dnes se cítím dobře, protože svítí slunce. - Today I feel good because the sun is shining.

cítit se = to feel (emotionally / physically)
- Cítím se dobře. = I feel good.
cítit (without se) = to feel/sense something, or to smell
- Cítím bolest. = I feel pain.
- Cítím kouř. = I smell smoke.

In the meaning "I feel good/bad/sick, etc.", you normally need se:
✅ Dnes se cítím dobře.
❌ Dnes cítím dobře. (sounds wrong / incomplete in this context)

Why is it dobře and not dobrý in cítím se dobře?

Dobrý is an adjective: "good" describing a noun (good day, good man, etc.).
Dobře is an adverb: "well" describing how something happens.

After cítit se, you use the adverb:

Cítím se dobře. = I feel well / good.
Dobrý člověk. = a good person. (adjective, not used here)

So here dobře describes how you feel, not what noun is good.

Can I move dnes to another position, like Cítím se dnes dobře?

Yes. Dnes (today) is quite flexible:

Dnes se cítím dobře. (neutral, very common)
Cítím se dnes dobře. (also fine; slight emphasis on today)
Cítím se dobře dnes. (possible, but less usual; sounds a bit marked)

All three are understandable; the first one is the most natural everyday word order.

Why is there no já (“I”) in Dnes se cítím dobře?

Czech usually drops subject pronouns, because the verb ending already shows the person:

cítím = I feel
cítíš = you feel (singular)
cítí = he/she/it/they feel

So Dnes se cítím dobře already clearly means I feel good today.
You can add já for emphasis or contrast:

Já se dnes cítím dobře. = I feel good today (maybe others don’t).

In protože svítí slunce, why is there no verb meaning “is”, like “is shining”?

In Czech, svítit already means “to shine / to be shining”.
You don’t need an extra “to be” verb:

svítí slunce = the sun shines / the sun is shining
(not je svítí slunce)

So protože svítí slunce covers both English meanings:

because the sun shines
because the sun is shining

What is the subject in protože svítí slunce? Why is the noun after the verb?

The subject is slunce (the sun).
Czech word order is flexible, and the subject can come after the verb:

Slunce svítí. = The sun is shining.
Svítí slunce. = The sun is shining. (more neutral/“it is the sun that’s shining”)

In protože svítí slunce, the verb–subject order is very natural. The grammar still works because verb endings and context show what is subject and what is verb.

Is there any difference between protože svítí slunce and protože slunce svítí?

The basic meaning is the same: because the sun is shining.

The difference is just in nuance and rhythm:

protože svítí slunce – slightly more neutral, common in speech.
protože slunce svítí – can put a bit more emphasis on slunce (“because the sun is shining”).

Both are correct and natural.

Can I leave out slunce and just say protože svítí?

Yes, in context you often can:

Dnes se cítím dobře, protože svítí.

This usually means “because the sun is shining / because it’s sunny”.
Czech will understand svítí here as “(the sun) is shining” if that makes sense in the situation. If the context is unclear, adding slunce makes it explicit.

Why is there a comma before protože?

In Czech, a comma is almost always required before a subordinate clause starting with protože (“because”):

Dnes se cítím dobře, protože svítí slunce.

The main clause is Dnes se cítím dobře, and protože svítí slunce is the subordinate clause giving the reason. Between those two, Czech spelling rules require a comma.

Can I say Dnes je mi dobře instead of Dnes se cítím dobře? Is there a difference?

Yes, you can, and both are very common:

Dnes se cítím dobře. = I feel good today.
Dnes je mi dobře. (literally “today is to me good”) = I feel well / I’m doing well today.

Nuance:

je mi dobře often focuses on your state/health/comfort (I’m fine, I’m OK).
cítím se dobře is slightly more about your subjective feeling.

In many everyday situations, they are interchangeable.