A:移液时,不慎将液体流到瓶外
B:容量瓶中原有少量的蒸馏水
C:容量瓶盛过Na2CO3溶液,使用前未洗涤
D:定容时读数仰视
Progress suggests a person's ability to change the way he is living at the moment and it must ______ a better life and a better way of doing things.