What are the rules concering multiple verbs in one sentence in Spanish?

Question

For example, if i wanted to say something like:
I know he said he would take out the garbage today.

How would I go about doing it? Do I conjugate each verb seperately? Do I conjugate one and leave the rest in the infinitive? Or do I do something else?

Thank you from one very confused Spanish student.

Answer 1

I know he said he would take out the garbage today.

Sé que él dijo que sacaría la basura hoy.

Conjugate each verb depending on its tense, because each verb can refer to a different situation depending on the tense or mode.

Answer 2

I know he said he would take out the garbage today.

Yo sé que dijo que sacaría la basura hoy.

I know ~ simple present tense (sé)
he said ~ past preterite (dijo)
he would take out ~ conditional (sacaría)

The preterite of saber usually translates "found out"
Yo lo supe ayer. I found out about it yesterday.
Yo lo sabía siempre. I always knew it.

dijo is the irregular preterite of decir

You can look up the names of these tenses in any Spanish textbook in the index at the end of the book.

Answer 3

I know he said he would take out the garbage today.

Yo sé que dijo que sacaría la basura hoy.
or
Yo sé que dijo que hoy sacaría la basura.