- Master que (that), the most common Spanish conjunction
- Use porque (because) to explain reasons and causes
- Understand aunque (although) with indicative vs subjunctive
- Apply time conjunctions: cuando, mientras, hasta que
- Recognize which subordinating conjunctions trigger the subjunctive mood
← Back to Grammar
Subordinating Conjunctions: Que, Porque, Aunque, Cuando, Si
What You'll Learn
Overview / Usage
While coordinating conjunctions connect equal elements, subordinating conjunctions introduce dependent clauses that cannot stand alone. They show relationships like cause, time, condition, and purpose.
🔗 Key Subordinating Conjunctions
que
that
Creo que sí
I think so
porque
because
porque quiero
because I want to
aunque
although
aunque llueva
even if it rains
cuando
when
cuando llegues
when you arrive
si
if
si puedo
if I can
mientras
while
mientras como
while I eat
Understanding subordinating conjunctions is essential for building complex sentences and expressing nuanced ideas. Some of these conjunctions require the subjunctive mood, which we'll highlight throughout.
Structure & Formation
🟢 Part 1: QUE (That)
Que is the most common Spanish conjunction. It introduces clauses after verbs of thinking, saying, believing, knowing, wanting, and more.
After Verbs of Opinion/Belief
Creo que tienes razón
I think (that) you're right
Pienso que es verdad
I think (that) it's true
Me parece que está cerrado
It seems to me (that) it's closed
Espero que vengas
I hope (that) you come
+ subjunctive
After Verbs of Communication
Dice que viene mañana
He says (that) he's coming tomorrow
Me dijo que estaba ocupado
He told me (that) he was busy
Explica que es difícil
She explains (that) it's difficult
Prometo que lo haré
I promise (that) I'll do it
Note: Unlike English, Spanish rarely drops "que."
✗ Creo tienes razón
✓ Creo que tienes razón
✓ Creo que tienes razón
🔵 Part 2: PORQUE (Because)
Porque (one word) introduces the reason or cause for something. Don't confuse it with por qué (two words), which means "why."
Estudio porque quiero aprender
I study because I want to learn
No vine porque estaba enfermo
I didn't come because I was sick
Lo hago porque me gusta
I do it because I like it
Llegó tarde porque perdió el tren
He arrived late because he missed the train
Don't Confuse:
porque = because
Voy porque quiero
por qué = why
¿Por qué vas?
porqué = the reason (noun)
No sé el porqué
Alternative: COMO at Start of Sentence
When the cause comes first, use como (since/as) instead of porque:
Como no viniste, salimos sin ti
Since you didn't come, we left without you
Como estaba lloviendo, me quedé en casa
As it was raining, I stayed home
🟠 Part 3: AUNQUE (Although/Even If)
Aunque expresses concession - acknowledging something that contrasts with the main clause. The tricky part: it can take indicative OR subjunctive, with different meanings.
+ Indicative = Fact
The situation is real/known
Aunque llueve, salgo
Although it's raining (fact), I'm going out
Aunque es caro, lo compro
Although it's expensive (I know it is), I'm buying it
+ Subjunctive = Hypothetical
The situation may or may not happen
Aunque llueva, saldré
Even if it rains (it might), I'll go out
Aunque sea caro, lo compraré
Even if it's expensive (whatever the price), I'll buy it
🔴 Part 4: Time Conjunctions
Time conjunctions show when something happens. When referring to future events, they typically require the subjunctive.
CUANDO (When)
Cuando era niño, jugaba mucho
When I was a child, I played a lot
Past = indicative
Cuando llegues, llámame
When you arrive, call me
Future = subjunctive
Cuando tengo tiempo, leo
When I have time, I read
Habitual = indicative
MIENTRAS (While)
Leo mientras como
I read while I eat
Ella trabaja mientras él cocina
She works while he cooks
Mientras esperas, toma un café
While you wait, have a coffee
HASTA QUE (Until)
Espera hasta que llegue
Wait until he arrives
Future = subjunctive
Esperé hasta que llegó
I waited until he arrived
Past = indicative
No me voy hasta que termines
I'm not leaving until you finish
Future = subjunctive
🟣 Part 5: SI (If)
Si introduces conditional clauses. For a full exploration, see our page on conditional sentences (si clauses).
Si tienes tiempo, ven
If you have time, come
Real condition
Si tuviera dinero, viajaría
If I had money, I would travel
Hypothetical
Si puedo, te ayudo
If I can, I'll help you
Open possibility
Important: Never use present subjunctive after si.
✗ Si tengas tiempo (wrong!)
✓ Si tienes tiempo (indicative) or Si tuvieras tiempo (imperfect subjunctive)
✓ Si tienes tiempo (indicative) or Si tuvieras tiempo (imperfect subjunctive)
🔷 Part 6: Conjunctions That Always Require Subjunctive
These conjunctions always trigger the subjunctive because they express purpose, anticipation, or conditions that may not be realized.
para que
so that / in order that
Hablo despacio para que entiendas
I speak slowly so that you understand
antes de que
before
Llámame antes de que salgas
Call me before you leave
a menos que
unless
Voy a menos que llueva
I'm going unless it rains
sin que
without
Salió sin que lo viéramos
He left without us seeing him
con tal de que
provided that
Te ayudo con tal de que me pagues
I'll help you provided you pay me
a no ser que
unless
Vendrá a no ser que esté enfermo
He'll come unless he's sick
Memory Tip: These conjunctions all express something that hasn't happened yet or might not happen - that's why they need the subjunctive!
Examples
💬 Real-Life Conversation Examples
Using QUE
Espero que te guste el regalo
I hope you like the gift
Dicen que va a nevar
They say it's going to snow
Es importante que llegues a tiempo
It's important that you arrive on time
Sé que puedes hacerlo
I know you can do it
Using PORQUE / COMO
No fui porque estaba cansado
I didn't go because I was tired
Como no llamaste, me preocupé
Since you didn't call, I worried
Lo sé porque me lo dijo
I know because he told me
Como hace frío, lleva abrigo
Since it's cold, wear a coat
Using AUNQUE
Aunque estoy cansado, voy a ir
Although I'm tired, I'm going to go
Aunque llueva, iré a la playa
Even if it rains, I'll go to the beach
Lo compró aunque era caro
She bought it although it was expensive
Aunque no quieras, tienes que hacerlo
Even if you don't want to, you have to do it
Using Time Conjunctions
Te llamo cuando llegue a casa
I'll call you when I get home
Escucho música mientras trabajo
I listen to music while I work
Espérame hasta que vuelva
Wait for me until I return
Después de que comas, descansa
After you eat, rest
Using Purpose Conjunctions
Te lo explico para que entiendas
I'm explaining it so you understand
Vete antes de que sea tarde
Leave before it's late
No iré a menos que me invites
I won't go unless you invite me
Lo hizo sin que nadie lo supiera
He did it without anyone knowing
Gotchas / Common Mistakes
📝 Don't Drop "Que"!
Unlike English, Spanish almost always requires "que":
✗ Wrong:
Creo es verdad
✓ Correct:
Creo que es verdad
I think (that) it's true
⚠️ Porque vs Por qué
These look similar but have different meanings:
porque (one word) = because
Voy porque quiero
por qué (two words) = why
¿Por qué vas?
🔮 Future = Subjunctive!
Time conjunctions need subjunctive for future events:
Past (indicative):
Cuando llegó, comimos
When he arrived, we ate
Future (subjunctive):
Cuando llegue, comeremos
When he arrives, we'll eat
💡 AUNQUE: Fact vs Hypothetical
The mood changes the meaning:
Indicative (it's happening):
Aunque llueve, salgo
Although it's raining, I'm going out
Subjunctive (it might):
Aunque llueva, saldré
Even if it rains, I'll go out
🚫 Never Present Subjunctive After SI!
For "if" clauses, only use indicative or imperfect subjunctive:
✗ Wrong:
Si tenga tiempo...
✓ Correct:
Si tengo tiempo... (real)
Si tuviera tiempo... (hypothetical)
🎯 COMO at Sentence Start
Use "como" instead of "porque" when the reason comes first:
Reason at end:
Me quedé en casa porque llovía
Reason at start:
Como llovía, me quedé en casa
Quick Test / Mini Quiz
📝 Interactive Subordinating Conjunctions Quiz
Test your knowledge of Spanish subordinating conjunctions!
1
Complete: Creo ___ tienes razón (I think you're right)
2
Which is correct for 'because I want to'?
3
Complete: ___ no viniste, salimos sin ti (Since you didn't come...)
4
Te llamo cuando ___ (I'll call you when I arrive)
5
Which sentence is correct?
6
Hablo despacio para que ___ (I speak slowly so you understand)
7
'Aunque llueve' vs 'Aunque llueva' - what's the difference?
8
Complete: Espera ___ llegue (Wait until he arrives)
Useful Resources
Coming soon...