I.on [美 ɑn, ɔn, 英 ɒn]介词on often appears as the second element of certain verb structures in English (count on, lay on, sign on, etc). For translations, see the relevant verb entry (count, lay, sign, etc).
He succeeded in making his escapepossibly he was permitted to leave on account of his youth and immediately began a more rigorous campaign against autocracy.