—So it is. It's made _______ grapes, and they can be made _______ many other foods.

在自然界中，任何生物要生存下去，就得为获取足够的食物和空间而进行生存斗争，生物通过遗传、变异和____，就不断进化。

    This morning Jenny, Linda, Mary, Alice and Sally found five bags. Jenny found a brown bag in Classroom 208. In the bag is ____. Linda found a purple bag in Classroom 306.In the bag is ____. Mary found a green bag in Classroom 409.In the bag is ____.Alice found a red bag ____.In the bag is a yellow pencil. Sally found a blue bag ____.In the age is a watch.

《史记•楚世家》记载：（春秋时期）“（楚庄王）八年，伐陆军戎（在洛阳西南），遂至洛，观兵于周郊。周定王使王孙满劳楚王。楚王问鼎小大轻重。”这反映了当时（   ）

已知a的倒数为 $-\frac{3}{5}$ ，则a的值为（    ）