4. What is the principle of the Alexander technique? A. Physical tension shouldn’t be completely relieved.B. Familiar physical actions shouldn’t be done with much effort.C. The practice of the technique shouldn’t be attempted alone.D. The technique shouldn’t be combined with other exercises.5. What can we learn about Frederick Alexander? A. He managed to recover his vocal powers. B. He was eager to make a name for himself.C. He developed a form of exercise for actors. D. He had to leave home to develop his technique.6. What is the main idea of the passage?A. The occurrence of back pain is widespread.B. Alexander improved the technique to treat body pain.C. The Alexander technique helps overcome posture problems.D. People with back pain are victims of inappropriate postures.