下列关于过滤的叙述中，错误的一句是()。
A. 过滤开始时，应注意检查滤液是否澄清、透明
B. 如果滤液混浊，说明滤纸有破损，应重新折叠滤纸、重新过滤
C. 过滤结束前，用少量蒸馏水冲洗漏斗出口
D. 弃去少量初液
The biggest threat of this economic crisis is that______.
A. financial crisis is disappointing
B. many people have lost their jobs
C. economic recovery is slow in progress
D. people"s expectations are too optimistic
【C6】
A. extent
B. part
C. degree
D. volume
【C14】
A. welcome
B. oblige
C. greet
D. receive
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