ellos temblaban

they were shaking, they used to shake

→ temblar
tembl tremble; shake + aban 3rd-person plural imperfect (indicative or subjunctive)
verb · third plural · imperfect indicative Rare #32,756
they were shaking, they used to shake Imperfect tense (third person plural).
SP: Les temblaban las manos de miedo.
EN: Their hands were shaking with fear.
Conjugation of temblar
Indicative imperfect
SingularPlural
First temblaba —
Third temblaba temblaban
Subjunctive imperfect
SingularPlural
First temblaba —
Third temblaba temblaban

Sus piernas temblaban del miedo.

Her legs trembled with fear.

Y me temblaban las manos.

And my hands were trembling.

Sus manos temblaban.

His hands were trembling.

— Caché (Escondido) (2005)

Mis manos temblaban demasiado para enhebrar la aguja.

My hands were shaking too much to thread the needle.

Ella podía sentir cómo temblaban sus rodillas.

She could feel her knees trembling.

Sus manos temblaban ligeramente cuando se puso a hablar.

His hands trembled slightly when he began to speak.

Tom se dio cuenta de que a Mary le temblaban las manos.

Tom realized that Mary’s hands were trembling.

Los pobres chicos temblaban de miedo.

The poor boys were trembling with fear.