名人教英文：大量储备
to stock up on something
大量储备某些东西
maryam: have you seen the weather forecast?
玛丽安﹕你有没有看天气预报？
francis: no, i've been too busy to watch tv today.
法郎西斯﹕没有，我今天很忙，没有时间看电视。
maryam: well, they're forecasting heavy snow from wednesday on. it could last for a few days.
玛丽安﹕据他们预测，星期三开始，会下大雪，而且可能连续几天。
francis: oh, no! i haven't done my weekly shopping yet.
法郎西斯﹕啊，糟了。我每星期买一次东西，现在还未去买。
maryam: you'd better get down to the supermarket as soon as you can.
玛丽安﹕你最好尽快去超级市场。
francis: you bet. i'm going to stock up on essentials like bread and milk in case the snow lasts longer than expected.
法郎西斯﹕这个自然。我会多买些面包、牛奶等必需品作储备，以防下雪的日子比预测要长。
to stock up on something是「大量储备某些东西」，那on改作with也可以；假如不说明储备什么，则只须说to stock up，例如﹕(1) we will stock up on/with firewood for the coming winter（冬天将临，我们会多储备木柴）。(2) did you stock up for the lunar new year holidays?（农历新年之前，你有没有多储备些物品？）
essential、necessity两字，都可以译做「必需品」，但essential所说的东西，比necessity更加不可缺乏，例如﹕(1) food and warm clothing are essentials when you are in the polar regions（在南北极地区，食物和温暖的衣服，都不可或缺）。(2) a car is not a luxury but a necessity when you live in the country（住在乡间，汽车就不是奢侈品，而是必需品）。形容词essential和necessary的分别，和名词essential和necessity相同，即essential所说的「必要」，比necessary更为强烈。
you bet直译是「你打赌」，但俗语常用这两字表示「的确」或「当然」，等于certainly，例如﹕"we are going to have a cup of coffee. would you like to join us?" "you bet."（「我们去喝咖啡。你想不想一起去？」「当然想。」）
留意it could last for a few days这一句。last解作「持续」，其后可用for带出一段时间，但不用for也可以，例如﹕the rain lasted (for) several hours（连续下了几小时雨）。