1）わたしはおこった。(WATASHI WA OKOTTA) = I got mad. 2）わたしはおこられた。(WATASHI WA OKORARETA) = Someone got mad at me. (I was being mad.)
3）おすしをたべた。(OSUSHI O TABETA) = I ate Sushi. 4）おすしをたべられた。(OSUSHI O TABERARETA) Sushi was eaten.
5）へやをそうじした。(SOUJI O SHITA) = I cleaned a room. 6）へやをそうじされた。(SOUJI O SARETA) = A room was cleaned.
No. 2,4,6 are all passive. Passive means that the action is being directed towards the speaker. Please read the Grammar section (Part 5) /Course 5 Lesson 2 and see how it is conjugated. する (SURU = to do) is an irregular verb, so you just have to memorize される (SARERU) as the passive verb form.
You list: heya wo souji sareta - as the room was cleaned (passive). But I thought that with a passive verb the direct object in the first example becomes the subject and thus the use of 'ga' is appropriate....
heya ga soujia sareta - the room was cleaned. Is this not correct, or is the 'wo' form correct? I hope the 'ga' form is correct or i've been using this incorrectly for a while :(