| Persona | imperfect | conditional | future | subjunctive | present | preterite |
|---|---|---|---|---|---|---|
| yo | debía | debería | deberé | deba | debo | debí |
| tú | debías | deberías | deberás | debas | debes | debiste |
| él / ella | debía | debería | deberá | deba | debe | debió |
| nosotros | debíamos | deberíamos | deberemos | debamos | debemos | debimos |
| ustedes | debían | deberían | deberán | deban | deben | debieron |
In Spain: vosotros form— imperfect: debíais, conditional: deberíais, future: deberéis, subjunctive: debáis, present: debéis, preterite: debisteis
The 'vosotros' form is used in Spain for informal plural address. In Latin America, 'ustedes' is used for both formal and informal plural.
You must study more if you want to pass the exam.
I owe my brother twenty dollars.
You should call your parents more often.
When I was young, I had to help at home every day.
It must have been an incredible trip.
I don't think we should go out in this storm.
Next month I will have to pay the university tuition.
to have to, must (strong obligation)
must, to probably be (supposition or probability)
to owe money
as it should be, properly