To express that something must be done—like following rules at border control—Italian frequently uses a special passive voice called the passivo di necessità (passive of necessity).
Forming the passive of necessity
Instead of using the verb dovere (must), this construction uses the simple tenses of andare (to go) followed by a past participle. Even though it uses the verb "to go," it translates to "must be [done]".
Since this is a passive sentence, the thing receiving the action is the subject. The verb andare is usually conjugated in the third person: va for a singular subject, or vanno for a plural subject.
Crucially, the past participle must agree in gender and number with that subject:
| The visa must be checked by the official. | Il visto va controllato dal funzionario. |
| The passport and the visa must be shown at the border. | Il passaporto e il visto vanno esibiti al confine. |
Border control rules
You will hear this structure constantly when officials explain requirements for inspecting bags and stamping documents.
| Every bag must be inspected carefully. | Ogni bagaglio va ispezionato attentamente. |
| These documents must be stamped immediately. | Questi documenti vanno timbrati immediatamente. |
When dealing with customs, you might need to pay a duty (il dazio) or risk having prohibited merchandise confiscated. Notice again how the past participle matches the subject (la merce is feminine singular, so we use sequestrata):
| The duty must be paid even if you show the invoice. | Il dazio va pagato anche se esibisce la fattura. |
| The prohibited merchandise must be confiscated. | La merce vietata va sequestrata. |
Even if you are just passing through, your transit tickets and forms will still need to be validated (convalidati).
| The transit ticket must be validated before leaving. | Il biglietto di transito va convalidato prima di partire. |
| The forms must be validated and stamped. | I moduli vanno convalidati e timbrati. |