The earth could be younger and took more than three times longer to form than thought, according to a new study.
A. favorably
B. deliberately
C. practically
D. previously
网友回答
A. favorably
B. deliberately
C. practically
(答案→)D. previously
解析：按新研究，地球比以前认为可能更年轻，形成多花了三倍多时间。A支持地有利地B有意地C实用实践地D先前地。