695. By 1940, the pilot Jacqueline Cochran held seventeen official national and
international speed records, and she earned them at a time when aviation was still
so new for many of the planes she flew to be of dangerously experimental design.
A. and she earned them at a time when aviation was still so new for many of the planes she flew to be
B. earning them at a time that aviation was still so new for many of the planes she flew to be
C. earning these at a time where aviation was still so new that many of the planes she flew were
D. earned at a time in which aviation was still so new such that many of the planes she flew were
E. earned at a time when aviation was still so new that many of the planes she flew were
正确答案是E
og解释了一下为什么选择were不选择to be但是我完全没理解orz
"In addition, the causal relationship between aviation being new and planes being of experimental design is more effectively
communicated by the structure so new that many X were Y, not by the structure so new for many X to be Y"