初学者一般不带旋转的发球技术是 ？
A. 平击发球
B. 正手发奔球
C. 反手发急上旋球
D. 拉弧圈球
准备姿势脚应该如何 ？
A. 前倾
B. 后仰
C. 竖直
D. 无所谓
Her anxiety about the ever-rising price of commodities was____the stress she felt about her forthcoming retirement.
One of the biggest problems for immigrants everywhere is whether they will be about to____with the local people effectively.
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