2 I think the invitations should be ___________ (send) by registered post.

Passive Voice Explanation

The passive voice is used to show what is done to the subject of the sentence. It is formed using a form of the verb 'to be' + the past participle of the main verb. Modal verbs like 'should' are followed by 'be' in the passive voice, then the past participle.

Solution:

The sentence uses the modal verb 'should'. The structure for the passive voice with modal verbs is: modal verb + be + past participle.

• The modal verb is 'should'.
• The verb is 'send'.
• The past participle of 'send' is 'sent'.

Therefore, the correct passive form is 'should be sent'.

Answer: should be sent