The verb zijn is used in more different ways than any other verb. As an independent verb, it functions as the link verb 'to be'. Further, it is often used as the auxiliary verb before a past participle.
Simple present:
| ik
| ben
| we
| zijn
|
| je
| bent
| jullie
| zijn
|
| hij
| is
| ze
| zijn
|
Simple past:
| ik
| was
| we
| waren
|
| je
| was
| jullie
| waren
|
| hij
| was
| ze
| waren
|
Past participle: geweest
Note that the examples above give you the unstressed personal pronouns. Some pronouns change when they are stressed in a phrase: je/jij, we/wij, ze/zij (both singular and plural).