The passive is always formed with the verb 'be' in the appropriate tense + the past participle of the verb Active voice - His parents have exposed him to many languages. The verb 'expose' is in present perfect tense. To make passive, use the verb 'be' in that same tense + the past participle of the verb. 'Be' in present perfect = have/has been. Past participle of 'expose' = exposed. Passive voice - He has been exposed to many languages. Any tense can be passive voice.

You can use the passive with any tense. - is exposed to - was exposed to - will be exposed to - has been exposed to - had been exposed to - will have been exposed to You use -ed because that's simply how you form passives: [to be] + [verb]-ed. Passives are never formed with -ing.

I love yo learn Germany contact if you want yo help me.