四、设有R(A，B，C，D，E，P)，R的函数依赖集F={A→D，E→D，D→B，BC→D，DC→A}。
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五、设有关系模式R(A, B, C, D), F={AB → C, C → D, D → A}
________(天气如何）this summer in Qingdao?
A. What does it look like
B. What's it look like
C. What weather does it like
D. What's the weather like
It’s sunny and clear these days. And________（气温舒适）.
A. the temperature is good
B. the weather is cozy
C. the temperature is comfortable
D. it is good temperature
________(预计有微风）the next two days.
A slight wind is due to
B. A light wind is expected for
C. A light snow is wished for
D. a slight wind is expect to
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