Ancient man attempted to change the weather by using magic.
While experience taught him this was impossible,                     __1__
he tried to forecast weather conditions. Even earlier in                 __2__
1000 were weather seers in Babylon----and priests
clever enough to denounce as frauds those predicted               __3__
the weather a year in the advance. Some forecasters used          __4__
methods that seemed to take no connection with the actual         __5__
factors controlled the weather. Chickens and other animals        __6__
were sacrificed and their intestines poked to find signs
indicating rain and drought. Somewhat more scientific were        __7__
predictions based on vegetation:"Onion's skin very thin ,mild
weather coming in. Onion's skin thick and tough, coming
weather is cold and rough." Insects and animals were also         __8__
favorite weather clues: "Before the glowworm lights his lamp,     __9__
then the air is always damp ." "If spiders their cobwebs forsake ,
the weather will for certain break ." "If frogs remained in pools ,
the weather will be fine . If they were seen on rocks,                 __10__
rain and cold were due." It's difficult to say whether this rhyme
should be taken seriously : " Hark , I hear the asses bray .
Me thinks we'll have some rain today ."

答案详解:
1.While-When或After.本句的this指代的是to change the weather by using magic. when/after 引导时间状语
r是early的比较级,其后应有than
之后加引导定语从句
4. 删除advance前的 advance为习语
5. connection with 为习语
6. controlled-controlling或在controlled前加that/lling the weather 或that/which controlled the weather做定语修饰the actual factors
7. 和draught只能是二者之一
8. 删除is.与上文平衡,均为省略句
9. before-when/if.条件句
10. 引导的是条件句用的是remained一般过去时来源