自然选育过程中采取土样时主要选择()之间的土壤
A.3-10cm
B.5-15cm
C.10-15cm
D.10-20cm
参考答案:B
Wang Feng ____ the Great Green Wall with many other people.[ ]
A. works on
B. works at
C. works out
D. works for
孕满42周及以上分娩者称为( )。
A.早产B.足月产C.过期产D.滞产E.难产