在显微镜下看到的像是一个倒像．如果将写有“p”字的透明纸片放在载物台上，制成玻片标本．用显微镜观察时，在视野里看到的将是（  ）

    An English gent leman always takes an umbrella and wears a hat. Why? In England, it rains often. The rain comes at any time, so an umbrella is necessary (必要的) in people's life. English gentlemen love to take a long black umbrella. It is useful when the rain comes. And it is also a style. The hat plays an important part in their life too. If two men meet in the street,  they take off (脱掉)  their hats to show their respect (尊重) to each other. If a man visits his friend, he takes off his hat frst when he gets into the room. If he goes to a party, he can only put the hat on his chair, but not on the table. You don't have the two things, but you can still (仍然) be a gentleman. Always be nice to others and be ready to help others. Show your respect and love to old people, women and children. Never shout. Never lose your temper (发脾气).

要想使 $\frac{a}{13}$ 是假分数， $\frac{a}{14}$ 是真分数，a是____．