重點講解：
1. beware of
小心；提防；當心；注意；
eg. Beware of being too impatient with others.
注意不要對他人太沒有耐心。
eg. Motorists were warned to beware of slippery conditions.
駕駛員接到提醒當心道路濕滑。
2.take advantage of
占…的便宜；欺騙；捉弄；
eg. It never occurred to me to take advantage of him.
我決沒有想到過要占他的便宜。
eg. He's joining the club in order to take advantage of the others.
他入會是來揩油的。
3. mark down
減價；降低…的價錢；
eg. Retailers will have to mark down prices sharply to bring in sales.
零售商將不得不為了提高銷量而大幅降價。
eg. Clothes are the best bargain, with many items marked down.
買衣服是最劃算的，許多衣服都降價了。