dedicated 努力工作的, 专注的, 投入的 = working hard at sth because it is important to you, 是committed 的同义词; 从英语释义看指的是人的工作态度 They are dedicated to their work.
从英语释义看指的是人的devoted 挚爱的, 忠诚的 = having great love for sb/sth and being loyal to them 从英语释义看指的是人的内在品质 They are devoted to their children/work.
be dedicated to / devoted to doing sth 都正确, 只不过意思有区别。