坐标磨床的运动有()、砂轮的行星运动和砂轮直线往复运动。
参考答案:砂轮自转
Find out the mistakes and correct them. 找出错误并改正。
( ) 1. I have to put on my boots on a rain day.
A B C
( ) 2. Li Ming is writing an letter in the corner.
( ) 3. The peas are in the stove.
( ) 4. I'm a 12 year old boy.
( ) 5. Danny, you should sing soft.
灌溉次数及灌溉量最好是()。
A、越多越好
B、一天一次
C、一天多次
D、土壤水分不足时就立即浇水,灌水量以能使水分浸润根系为宜