Pb3 And His Robot, Petra, Are With Their Earth Friends, Ben And Susi Finding Out About Life At The Beach. Suddenly The Evil Oos Arrive In Their Spaceship And Try To Catch Them. In Their Hurry To Escape The Two Ets Dive Into The Water And Discover Another World Under The Sea. In Their Attempt To Help Some Grey Fish They Put Them In Great Danger. Their Friends Help Them To Understand But Can They Put The Situation Right Again? Syllabus: The Sea, The Beach, The Colours, Verbs Of Motion, The World Around Us. Present Indicative, Prepositions, Imperatives, Possessive Pronouns.