Directions: For each blank in the following passage there are four words or phrases marked A, B, C and D. Fill in each blank with the word or phrase that fits the context.
A detailed study of biological diversity（多样性）in town and city gardens has found that they offer a vital refuge for animals and plants. It has also fund that many of the ideas about wildlife gardening are not1.In fact, small gardens are just as good as big gardens at2wildlife, suburban gardens are not always better than city gardens and non-native plants are not always harmful to native insects and birds. Britain's 16,000,000 gardens are a refuge for hundreds of species of animals and plants that would find it3to survive onintensively （精细地）farmed land. According to the study, gardens are amazingly varied even compared to4environments that are good for wildlife. Small gardens are more interesting5they vary a great deal in botanical environment, All the wildlife responds to the variation.
Ken Thompson of Sheffield University was involved n the first detailed study of the6living in British gardens when he and his colleagues surveyed7gardens in Sheffield. They really found a(n)8diversity of plants and animals. They also identified a range of simple9that improved a garden's environment for wildlife. The top thing is to grow more big trees as these greatly10the volume of vegetation in the garden and a lot of11means a lot of places to live and a lot of things to eat.12, create a pond for insects and frogs. Think before stocking it with fish which will eat insect eggs. Also, it is not wise to light up the garden at night with bright lawn lamps, which will13many night creatures, Finally, don't be too tidy: don't be14to clear up everything when the garden stops flowering. Just15a bit of things lying around.
To sum up, people who want to turn their gardens into wildlife refuges should  64  and let the grass grow tall, the flowers turn to seed and trees expand skyward.

1．	A．true          B．basic         C．vivid         D．simple

2．	A．selecting      B．importing     C．offering       D．attracting

3．	A．impossible       B．illegal          C．lucky         D．convenient

4．	A．peaceful      B．warm              C．natural         D．clean

5．	A．before         B．unless          C．but           D．because

6．	A．wildlife       B．men         C．germ         D．pet

7．	A．confusing     B．complete      C．surprising     D．orderly

8．	A．measures     B．standards     C．services       D．functions

9．	A．occupy        B．increase       C．limit         D．reduce

10．	A．vegetation     B．reservation       C．preparation      D．decoration

11．	A．By contrast      B．As a result          C．In other words  D．In addition

12．	A．block          B．disturb         C．benefit         D．protect

13．	A．in a mess     B．in a way      C．in a hurry     D．in a while

14．	A．forget          B．remove        C．avoid         D．leave

15．	A．escape         B．relax         C．strive         D．retire