含有2个羧基的氨基酸是（）
A.丝氨酸
B.酪氨酸
C.谷氨酸
D.赖氨酸
E.苏氨酸
参考答案：C
The shop assistant promised me that the material ____, and what she said ___ to be true .
would be dried easily ; was proved B. will be dried easily ; was proved
C. dried easily ; proved D. dried easy ; proved
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