电火花线切割加工主要应用在哪些方面?
参考答案:
①加工模具;
②电火花成形加工用的电极;
③试制新产品;
④贵重的金属材料
There isn't ________ water in the glass. Let's go and get some. [ ]
A. many
B. lots
C. any
D. some
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