pp2-64 对比６１题 请高手指点啊，好不容易才发上来的啊５５５

opensq

61. (27648-!-item-!-188;#058&003611)

Researchers in Germany have unearthed 400,000-year-old wooden spears from what it appears   was an ancient lakeshore hunting ground as stunning evidence of human ancestors who 　systematically hunted big game much earlier than believed.

(D) appears to be an ancient lakeshore hunting ground, stunning evidence that human ancestors 对
(E) appears that it is an ancient lakeshore hunting ground, stunning evidence of human ancestors　who　　错　

64 .
The majority of scientists believe that to reduce and stabilize atmospheric concentrations of carbon  dioxide, emissions must be cut at the source by fossil fuels that are burned more efficiently and, in  some cases, by alternatives such as hydrogen fuel cells that can replace fossil fuels altogether.

(A) fossil fuels that are burned more efficiently and, in some cases, by alternatives such as 　hydrogen fuel cells that can replace fossil fuels altogether　错
俩个给的答案都是说错在从句掩埋，但是上面那个６１题正确答案用的是that,而下面却说６４说that从句掩埋，不知道这个从句掩埋到底是怎么回事，为什么一个that可以，一个that却错

opensq

自己顶啊，修改了好几遍才弄好，大家帮帮忙吧