I wonder if you can help me when I get stuck.

　　get stuck: be in trouble 遇到麻煩

　　E.g. He always comes to my rescue whenever I get stuck.

　　每次我遇到麻煩都是他幫我解圍。

　　Let me know at any time.

　　Let me know: tell me or inform me 告訴，通知

　　E.g. when you get to Beijing, please let me know and I’ll meet you at the airport.

　　你到了北京告訴我一聲，我去機(jī)場接你。

　　As we cross the threshold into the next century…knowledge based economy.

　　threshold n.. 門檻、門欄、(喻)開始

　　E.g. Mind you step when you cross the threshold. (mind your head 小心碰頭)

　　過門檻的時候小心點(diǎn).

　　He was graduated last year and now is on the threshold of his career.

　　他去年剛剛畢業(yè),現(xiàn)在正是事業(yè)的起步階段.

　　Knowledge-based economy 知識經(jīng)濟(jì)

　　E.g. Market-based /driven economy 市場經(jīng)濟(jì)

　　State-owned enterprises 國有企業(yè)(S0E)

　　overseas-funded enterprises外資企業(yè)

　　Snow-covered mountain雪山