阅读下面短文，回答下列五道题
汉字究竟起源于何时呢？我认为，这可以以西安半坡村遗址距今的年代为指标。半坡遗址的年代，距今有6000年左右。我认为，这也就是汉字发展的历史。
半坡遗址是新石器时代仰韶文化的典型，以红质黑纹的彩陶为其特征。其后的龙山文化，则以薄质坚硬的黑陶为其特征。值得注意的是：半坡彩陶上每每有一些类似文字的简单刻画，和器物上的花纹判然不同。黑陶上也有这种刻画，但为数不多。刻画的意义至今虽尚未阐明，但无疑是具有文字性质的符号，如花押或者族徽之类。我国后来的器物上，无论是陶器、铜器或者其他成品，有“物勒工名”的传统，特别是殷代的青铜上有一些表示族徽的刻画文字，和这些符号极为相类似。由后以例前，也就如由黄河下游以溯源于星宿海，彩陶上的那些刻画符号，可以肯定地说就是我国文字的起源，或者是我国原始文字的孑遗。
同样值得注意的是彩陶上的花纹。结构虽然简单，而笔触颇为精巧，具有引入的魅力。其中有些绘画，如人形、人面形、人着长衫形、鱼形、首形、鸟形、草木形、轮形(或以为太阳)等等，画得颇为得心应手，看来显然在使用柔软形的笔了。有人以为这些绘画是当时的象形文字，其说不可靠。当时是应该有象形文字的，但这些图形，就其部位而言，确是花纹，而不是文字。
在陶器上既有类似文字的刻画，又有使用颜料和柔软形的笔所绘画的花纹，不可能否认在别的质地上，如竹木之类，已经在用笔来书写初步的文字：只是这种质地是容易毁灭的，在今天很难有实物保留下来。如果在某种情况之下，幸运的还有万一的保留，那就有待于考古工作的进一步发掘和幸运的发现了。
总之，在我看来，彩陶和黑陶上的刻画符号应该是汉字的原始阶段。创造它们的是劳动人民，形式是草率急就的。
(节选自郭沫若《古代文字之辩证的发展》)
How many teeth have you had filled in the past two years If you follow the advice of Dr. Faustick, you may be able to reduce tire number of your visits to a dentist. Dr. Faustick conducted a two-year survey to find out how to prevent or reduce dental decay. 946 students took part in an experiment. 523 students cleaned their teeth within ten minutes of eating: when possibly they used a toothbrush, when this was impossible they washed their mouth thoroughly with water. The remaining 423 students merely cleaned their teeth when they went to bed and when they got up in the morning. All the students had their teeth X-rayed at the end of the first and second years. At the end of the first year, the night and morning group had. three times as many decayed teeth as the former group. Dr. Faustick has cleaned his teeth after each meal for thirteen years and has not had a single decayed tooth. He pointed out that sugar is a major agent in dental decay. Particularly the sugar in sweets, cake
A. Brush your teeth in the morning.
B. Brush your teeth in the evening.
C. Clean your teeth shortly after eating.
D. Have your teeth X-rayed.
我来回答:
