重點講解：
1. prop up 支撐；維持；
例句：On the Stock Exchange, aggressive buying propped the market up.
在證券交易所，市場在大量買單的推動下有所上揚HXLdeX9+_u;^5B7。
2. block off 封閉，封住（門、窗或通道）；
例句：Heavy snow has blocked off traffic on the motorways.
大雪阻礙了高速公路上的交通+6HWdkWPftryoicQ%。
3. in advance 提前；事先；
例句：As long as you've paid in advance we won't charge you for delivery.
只要你預先付款，我們就不收你送貨費-kRzyiZq[OZ,,Nq。
4. give away 贈送；捐贈；
例句：We have six copies of the book to give away.
這本書我們要贈送6本出去A;M@EL+9rA@|U*VD。
5. as of 在…時；從…起；自…始；
例句：As of now we don't know much about Mars.
目前我們對火星還知之甚少5;!r0FphGcuvX]h5@。
6. stand at 處于（某一水平）；
例句：Your temperature stands at 100°F.
測得你的體溫為100華氏度+d+ouB9GL~%kW;。