为了适应数控加工需要，提高产品质量和效率，应推广使用模化和标准化刀具。
参考答案：对
Our favourite food __________ dumpings.[ ]
A. am
B. is
C. are
D. be
I walked in our garden, ________Tom and Jim were tying a big sign onto one of the trees.
A．which
B．when
C．where
D．that
