Dandelions（蒲公英）arecommonweedsthatgrowinmanyplacesaround...

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Dandelions（蒲公英） are common weeds that grow in many places around the world. In different ___21___, dandelions take different shapes. Scientists have long ___22___ that different habitats led to the creation of ___23___ species, and that differences in form are actual proof of different species. ___24___, according to Turesson, it is also possible that a ___25___ species takes different shapes dependent on the habitats it ___26___ in. To study this, I have looked at two dandelions growing in different habitats. The one, ____27____ I will call Dandelion 1, grows in a grass field that lies in the ___28___. The other Dandelion, Dandelion 2, grows in the shadow, eg ___29___ the trees or behind a shed. The grass field is hot and ___30___. The shadow is cool and wet. So, what are the ___31___ between Dandelion 1 and 2?

Dandelion 1 is dark green, and its ____32____ are short and quite thick. Most of the leaves lie ___33___ on the surrounding grass. The flowers are short. Dandelion 2, on the other hand, looks very differently. The leaves are long and ____34____green, Most leaves stand in a vertical position. The flowers also ___35___ tall.

Dandelion 2 ___36___ strong and tall. It is clear that it grows very well in the ___37___, and that has enough ____38____ and space to grow into a big plant. Dandelion 1, on the other hand, is small and dark. It seems that the ____39____ in the grassland make it difficult for this dandelion to grow into a big plant.

____40____, the conditions in the two different habitats result in different shapes for these dandelions. For Dandelion 1, the sun makes the grass field hot and dry. In order to save water, it grows short and thick leaves.

21. A. houses B. habitats C. parks D. countries

22. A. disagreed B. provided C. believed D. calculated

23. A. new B. good C. old D. bad

24. A. However B. Therefore C. Thus D. Otherwise...

25. A. same B. different C. strange D. single

26. A. plants B. works C. takes D. grows

27. A. what B. which C. that D. when

28. A. world B. mountain C. sun D. valley

29. A. under B. over C. upon D. between

30. A. Humid B. Wet C. Soft D. dry

31. A. similarities B. advantages C. differences D. disadvantages

32. A. seeds B. leaves C. weeds D. woods