His studies on the life and contributions of Isaac Newton to optics______versatile and impressive.
A. is
B. are
C. will be
D. be
找规律填数字是一项很有趣的活动,特别锻炼观察和思考能力。下列选项中,填入数列“1、2、9、33、()”空缺处的数字,正确的是()。
A. 122
B. 124
C. 126
D. 128
When he was the director in the plastic plant, he ______ together with the workers.
A. has worked
B. had worked
C. had been worked
D. used to work
幼儿认真完整的听完老师讲的故事,这一现象反映了幼儿注意的什么特征?()
A. 注意的选择性
B. 注意的广度
C. 注意的稳定性
D. 注意的分配