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【简答题】
观察下面的青蛙发育过程图，回答下列问题： ⑴从图中的发育过程看，青蛙的发育属于____________发育。 (2)青蛙的精子和卵细胞在_________中结合，形成受精卵，完成受精作用，这种受精方式叫_______________。 ⑶青蛙的_________和_______________都离不开水，而且皮肤裸露，无法防止体内_________的散失，只能生活在潮湿的环境中，所以两栖动物不是真正的动物，而是脊椎动物由水生向过渡的一个类群。
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【简答题】From the text we can infer that [ A] the commitment to improve the capacities of the poor will hardly be made. [ B] the investment in educational ,medical and job programs is non-profitable. [ C] the ...
【简答题】We have one caveat on this PO.
【单选题】询问客人是否需要添加食品时应说( ) 。 prefix="o" ns="urn:schemas-microsoft-com:office:office" ?xml:namespace>
A.
、还要饭吗
B.
、要哪种饮料 prefix="o" ns="urn:schemas-microsoft-com:office:office"? ?xml:namespace>
C.
、要汤吗
D.
、给您再添点饭吗 prefix="o" ns="urn:schemas-microsoft-com:office:office"? ?xml:namespace>
【单选题】We learn from the text that Edward Bannerman is probably
A.
an enthusiast in agricultural policy.
B.
a tough leader in social affairs.
C.
an doubter of spending on research.
D.
a pioneer in space exploration.
【单选题】We can conclude from the first two paragraphs that whether a male practices monogamy of polygamy depends on ______.
A.
the amount of nurturing the young
B.
the sex of offspring
C.
the attractiveness of his female partner
D.
the time of conception
【简答题】From the text we learn that the laser can_________ [A] cut a structure from a right position [ B ] design parts of a complex structure [ C] measure the distance between planets [ D] predict the moveme...
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