注浆料采用碳酸钠作为电解质，坯体致密且强度较大，用水玻璃作为电解质，获得比较疏松而强度较低的坯体。
参考答案：对
_____ Sandy was playing the piano, someone knocked at the door.[ ]
A: While
B: Before
C: After
D: Until
复合会计分录一般是指多借多贷的会计分录。( )
