Future tense (Irregular verbs) 2

The drop group vs the -d- group — Irregular future stems fall into two sub-patterns. The drop group drops the infinitive vowel: saber → sabr-, poder → podr-, querer → querr-, caber → cabr-, haber → habr-. The -d- group replaces the infinitive vowel with a d: poner → pondr-, tener → tendr-, venir → vendr-, valer → valdr-, salir → saldr-.

Decir and hacer are unique — Two verbs change completely: decir → dir- and hacer → har-. These don't fit either pattern above. Their future forms: diré, dirás, dirá… and haré, harás, hará… Given how common these verbs are, memorise these two as priority items.

Future irregular stems also appear in the conditional — The same irregular stems are used for the conditional tense — add conditional endings (-ía, -ías, -ía…) to the same stems: tendría, pondría, sabría, diría, haría. Learning the future irregular stems once gives you the conditional irregulars automatically.