First of all, you need to know the correct conjugation of the verb SER, and here it is: yo soy, tu eres, el/ella/usted es, nosotros somos, vosotros sois, ellos/ellas/ustedes son. Having that in mind, here are the correct answers: 2. Clara no es cubana = Clara is not Cuban. 3. Yo soy abogada = I am a lawyer. 4. Tu eres secretaria = You are a secretary.