数字同步网有哪三种同步方式？
参考答案：
数字同步网的三种同步方式为：位同步、群同步和网同步。
用所给单词的正确形式填空。
小题1:Since she _____ (come) here, she have visited many places in the city.
小题2:Do you have a hard time ______ (wait) for the taxi in the evening?
小题3:Students should speak to the teachers and parents _____( polite).
小题4:Don’t worry! I can look after _____(I).
小题5:There are six ______ (hundred) students in our school.
以下哪种作物不会产生离层，因而不会发生叶片脱落。（）
A．棉花
B．大豆
C．水稻
D．油菜
