()误差是由某些难以控制、无法避免的偶然因素造成的。
A.环境
B.操作
C.随机
D.可变
参考答案:C
句型转换。
1. Her brother has a ball. (改为一般疑问句)
_____ her brother _____ a ball?
2. My sister has a computer game. (改为否定句)
My sister _____ _____ a computer game.
3. Ann has a nice tennis racket. (对画线部分提问)
_____ _____ Ann _____?
4. Do you want to play soccer this afternoon? (改为祈使句)
_____ _____ soccer this afternoon.
5. My father doesn’t play tennis. (改为肯定句)
My father _______ tennis.
当Style属性为______时,组合框为简单组合框。
A.0
B.1
C.2
D.3