If: ba-

Basque has no separate word for "if". Instead, the prefix ba- is written together with the conjugated verb of the if clause.

Where ba- goes.

• With a main verb and an auxiliary, ba- goes on the auxiliary: etortzen da → etortzen bada (if he comes), ikusi duzu → ikusi baduzu (if you have seen it).
• With a one-word verb such as egon or jakin, ba- goes on that verb: badago (if it is there), badakizu (if you know).
• In a weather phrase, it goes on the auxiliary as usual: euria ari badu (if it is raining).

Order. The if clause usually comes first, then the result: Denbora badut, etorriko naiz. (If I have time, I will come.) The result can be a statement, a future or a command. For a future event, the if clause normally keeps the present form, just as English does: Bihar euria ari badu, etxean geratuko gara. (If it's raining tomorrow, we will stay at home.)

Negative conditions. Put ez in front of the ba- form: Nahi ez baduzu or Ez baduzu nahi (if you do not want to).

Two kinds of ba-. The same prefix also appears as affirmative ba-, as in Badakit (I do know). So badakizu can mean "you do know" or "if you know". The rest of the sentence tells you which: in Erantzuna badakizu, esan! (If you know the answer, say it!), a second clause depends on it, so it is a condition.

Optional baldin. You can add baldin to stress the condition. It can open the clause or sit right before the ba- verb: Baldin denbora baduzu, etorri or Denbora baldin baduzu, etorri. It is never required.

This entry covers real conditions, things that may well happen. Imagined situations such as "if I were rich" use different forms like banintz and banu.