disadvantage n. 不利，不利条件;
E.g. Depression is the third thing that works to my patients' disadvantage.
disappear. v. 消失
E.g. He saw something dark disappear behind the curtain of leaves.
disconnect. v. 分离
E.g. You should disconnect the wireless set before you make adjustments inside it.
2. di-,dif-, dis-： away，negative否定，分开，不
distrust. v. 不信任, 怀疑
E.g. What he saw there left him with a profound distrust of all political authority.
disassemble v. 拆开
E.g. We had to completely disassemble the engine to find the problem.
differentiate v. 区分
E.g. A child may not differentiate between his imagination and the real world.
illiterate n. 文盲;
E.g. Many senior managers are technologically illiterate.
illegitimate a. 非法的
E.g. The election was dismissed as illegitimate by the opposition.
E.g. Such measures would be highly impracticable and almost impossible to apply.
E.g. Parents fear they might overstep these invisible boundaries...
E.g. His behavior was becoming increasingly irrational.
E.g. He said that he was not tortured or maltreated during his detention...
E.g. Infections are more likely in those suffering from malnutrition.