"Siempre me despierto en la noche cuando pasa un tren cerca de mi casa." The sentence is grammatically correct.
Explanation:
"Siempre me despierto en la noche cuando pasa un tren cerca de mi casa." The sentence is grammatically correct. In English this means: I always wake up at night when a train passes by near my house.
First of all, the tense in the simple present is correct as the sentence refers to a situation that it's a habit. "Siempre" means "always", that's how we know this happens often.
