He has away the weekend.[ ]
A. gone；on
B. been；for
C. gone；for
D. went；at
答案：B
为核酸的一种，其化学结构名称为次黄嘌呤核酸的物质是()为肌肉组织中贮能和供能的物质，大部分含有高能磷酸键——磷酸肌酸的物质是()为肌苷与磷酸结合形式的物质是()为肌酸的代谢产物的物质是()为嘌呤分解代谢的终产物的物质是()
A．肌苷
B．肌苷酸
C．尿酸
D．肌酸
E．肌酐
--Be careful! You might fall into the water.
--Thank you. I____.I______ so close to the pool.
A．didn't know; am standing
B．don't know; am standing
C．didn’t know; was standing
D．didn't know;Would stand
