be interested doing/to do
    interested to do　　 對做某事感興趣，想了解某事。
    interested in doing　 對某種想法感興趣，doing 通常為想法。
    I shall be interested to know what happens. 我很想知道發(fā)生了什么事。 (想了解)
    I'm interested in working in Switzerland. Do you have any idea about that? 我對在瑞士工作感興趣。你想過這事嗎？　 (一種想法)
    mean to doing/to do
    mean to do　 打算、想
    mean doing　意味著
    I mean to go, but my father would not allow me to. 我想去，但是我父親不肯讓我去。
    To raise wage means increasing purchasing power. 贈(zèng)加工資意味著增加購買力。
    begin(start) doing/to do
    begin / start to do sth
    begin / start doing sth。
    1) 談及一項(xiàng)長期活動(dòng)或開始一種習(xí)慣時(shí)，使用doing。
    How old were you when you first started playing the piano? 你幾歲時(shí)開始彈鋼琴？
    2) begin, start用進(jìn)行時(shí)時(shí)，后面動(dòng)詞用不定式to do
    I was beginning to get angry.　我開始生起氣來。
    3) 在attempt, intend, begin, start 后接know, understand, realize這類動(dòng)詞時(shí)，常用不定式to do。
    I begin to understand the truth.　我開始明白真相。