Verbs are most frequently used in the active form. In the active form the subject performs the action described by the verb.
| Pigen spiser et æble. | The girl eats an apple. |
Pigen is the subject and spiser is the verb in the active form. The verb also has a passive form. In the passive form the subject is not active but passive.
| Et æble spises af pigen. | An apple is eaten by the girl. |
Et æble is the subject, spises is the verb in the passive form and af pigen is a prepositional phrase. Et æble is the subject, but of course it is not active.
The passive may be formed in two ways. Either by adding an -s at the end of the verb, or by using a form of to be and a past participle.
The passive form with the ending -s is used when the action described is a general phenomenon or something that happens frequently. This form is used in work instructions. If we are in the present, we add the ending -s to the infinitive. If we are in the past, we add an -s to the ending of the past tense form.
| Grøntsagerne koges i 15 min. | The vegetables are boiled for 15 mins. |
| Stoffet sys sammen i siderne. | The material is sewn together at the sides. |
| Postkassen tømtes kl. 9. | The postbox was emptied at 9.00. |
The passive form that has at blive plus a past participle (see 1.5 Present perfect) is used when we talk about an action that only happens once. In the spoken lanuage, blev, and not -s, is used most often when we are in the past, even though we talk about something that has happened many times.
| Et æble bliver spist af pigen. | An apple is being eaten by the girl. |
| Et æble blev spist af pigen. | An apple was eaten by the girl. |
Comparison:
In English, as opposed to Danish, the passive can only be formed in one way. The passive is formed by using a form of to be plus a past participle.