问题补充:
His brother aims to be of his parents by the time he is twenty.
A. innocent
B. beneficial
C. invisible
D. independent
答案:
A. innocent
B. beneficial
C. invisible
(答案→)D. independent
解析: 词义辨析。innocent 无辜的,无罪的;beneficial有益的;invisible 看不见的;independent独立的。句意:他弟弟打算在他20岁时能够离开父母独立。所以选D。