The Amazon rainforest is home to a great     1    (various) of plant life; however, its soil is    2       (surprising) poor in nutrients. In fact, the soil in the region cannot support agriculture for more than a few years. If a scientist is shown a report     3    (list) the nutrients of that soil, he or she will probably think that only desert plants can survive in it! Then why is the soil so poor in nutrients? For one thing, the rainy season has     4     impact on the soil. In this season, the water level can rise to more than 12 meters.     5     the water goes away, it takes away the nutrients in the soil. For another thing, due to the Amazon’s hot climate, it is difficult for the soil     6    (build) enough nutrients. Dead plants and animals     7    (break) down more quickly. The nutrients are soon taken in by the roots of the plants deep     8     the ground. As a result, most of the forest’s nutrients are locked up in the plants     9    (them), thus allowing them to grow at a(n)    10    (believable) speed.