【单选题】
在网络协议的三个基本要素中,_____是数据和控制信息的结构或格式。___
A. 语义
B. 语法
C. 服务
D. 词法
查看试卷,进入试卷练习
微信扫一扫,开始刷题

答案
B
解析
暂无解析
相关试题
【单选题】
在下面对OSI参考模型的数据链路层的功能特性描述中,哪一项是不正确的?___
A. 通过交换与路由,找到数据通过网络的最有效的路径
B. 数据链路层的主要任务是提供一种可靠的通过物理介质传输数据的方法
C. 将数据分解成帧,按顺序传输帧,并处理接收端发回的确认帧
D. Ethernet的数据链路层分为LLC和MAC子层,并在MAC子层使用CSMA/CD协议争用信道
【单选题】
下面属于TCP/IP协议族中网络互联层协议的是___。
A. IGMP、UDP、IP
B. IP、DNS、ICMP
C. ICMP、ARP、IP
D. FTP、IGMP、SMTP
【单选题】
Having practiced so many times, I feel very ___ of my ability to deliver the presentation successfully.
A. satisfied
B. incredible
C. confident
D. enthusiastic
【单选题】
The university decided to increase the ___ of the lecture hall, which has only 200 seats.
A. ability
B. capacity
C. facility
D. faculty
【单选题】
Smart phones – with cameras and color screens – can ___ images and data using wireless network technology.
A. evolve
B. depart
C. transmit
D. assure
【单选题】
Don’t take someone you get to know from the Internet to your house no matter how ___ he sounds.
A. bold
B. genuine
C. flexible
D. available
【单选题】
This kind of exercise will ___ your creativity, renew your energy, and unlock your potential.
A. bind
B. yield
C. embrace
D. stimulate
【单选题】
I’ll be happy to help you, ___ you won’t take up too much of my time.
A. as well as
B. as long as
C. as far as
D. as soon as
【单选题】
We teachers do not consider it wise to ___ our students with all sorts of exams, tests and quizzes.
A. load
B. annoy
C. sample
D. explore
【单选题】
He makes his students ___ knowledge through various kinds of interesting activities.
A. study
B. learn
C. achieve
D. acquire
【单选题】
For years, scientists have debated the ___ dangers of building another nuclear plant after the terrible accident.
A. available
B. potential
C. fascinating
D. genuine
【单选题】
It was a worthwhile attempt ___ it failed to achieve its purpose that we had hoped for.
A. in the end
B. now that
C. all at once
D. even though
【单选题】
Travel in space can be very exciting; ___, it can also be boring and lonely at times.
A. so
B. however
C. thus
D. therefore
【单选题】
Politicians should not ___ in business affairs that might affect their political judgment.
A. engage
B. embrace
C. depart
D. treasure
【单选题】
I wish to ___ a master’s degree in electric engineering after I graduate from college.
A. pledge
B. explore
C. pursue
D. approach
【单选题】
There is no greater importance ___ cultivating independence in children.
A. in
B. than
C. of
D. with
【单选题】
He has made it very clear ___ we should observe the new rules.
A. what
B. which
C. those
D. that
【单选题】
It was when I read his letter ___ I realized he had given me huge help.
A. that
B. then
C. before
D. after
【单选题】
Don’t worry too much, Jane. Your son ___ home already. Let’s go back and check it out.
A. returned
B. will return
C. has returned
D. may have returned
【单选题】
I believe friendship is an essential element of making a healthy, ___ life.
A. flexible
B. rewarding
C. wealthy
D. inquisitive
【单选题】
___ they have written about the behaviors of animals is hardly anything new.
A. That
B. This
C. What
D. Which
【单选题】
No other drugs are as good as this one; it must have been based on a(n) ___ formula (配方).
A. enormous
B. stimulating
C. unique
D. overwhelming
【单选题】
Mothers tend to be too ___ toward their children. They should let them see more of the worl D.
A. hopeful
B. protective
C. modest
D. encouraging
【单选题】
The investigation ___ evidence of a large-scale illegal trade in wild birds.
A. uncovered
B. outweighed
C. overwhelmed
D. evolved
【单选题】
Poor Laura! I feel so sorry for her. When she fell, she hurt her arm and, ___, broke her glasses.
A. in advance
B. in addition
C. over time
D. on the other hand
【单选题】
Showing some sense of humor can be a(n) ___ way to deal with some stressful situations.
A. genuine
B. available
C. effective
D. favorite
【单选题】
It will be worth the efforts even if you fail; the rewards you ___ will be great.
A. reap
B. boast
C. assure
D. cultivate
【单选题】
He suggested transporting the supplies by air. But it is absolutely ___, for it will cost too much.
A. unusual
B. uncertain
C. impractical
D. impressive
【单选题】
The newspaper didn’t mention the ___ of the damage caused by the fire.
A. range
B. level
C. extent
D. quantity
推荐试题
【单选题】
下列哪项不应看成是妊娠的确切象征___
A. B超显示宫腔内有胎囊
B. 超声多普勒法听到胎心音
C. 经腹壁触到胎儿肢体及胎头
D. 免疫学实验测出HCG
E. X线摄片见到胎儿骨骼影
【单选题】
患儿,女,8岁,因眼睑浮肿、肉眼血尿4天伴头痛以急性肾小球肾炎收住入院,现已住院2周,该患儿何时可以恢复正常生活___
A. 水肿消退,血压降至正常
B. 肉眼血尿消失
C. 血沉正常
D. Addis计数正常
E. 病后1~2个月
【单选题】
十二指肠溃疡疼痛的特点是___
A. 餐后即痛,持续2小时后缓解
B. 餐后1小时开始,持续2小时后缓解
C. 餐后2小时开始,持续2小时后缓解
D. 餐后3~4小时开始,进餐后缓解
E. 无规律性
【单选题】
下列关于恶性贫血的描述,错误的是___
A. 恶性贫血在我国罕见
B. 导致发病的间接因素是内因子缺
C. 患者常患有慢性萎缩性胃炎
D. 导致发病的直接因素是叶酸缺乏
E. 常伴有四肢麻木、乏力、共济失调等表现
【单选题】
应用复苏药物时选择给药方式的最佳顺序是___
A. 气管内给药、心内注射、静脉给药
B. 心内注射、静脉给药、气管内给药
C. 静脉给药、气管内给药、心内注射
D. 静脉给药、心内注射、气管内给药
E. 心内注射、气管内给药、静脉给药
【单选题】
小儿糖尿病全热量分三餐:早,中,晚以下哪项是正确的___
A. 2/5,2/5,1/5
B. 1/5,2/5.2/5
C. 2/5,1/5,2/5
D. 1/3,1/3,1/3
E. 1/4,2/4,1/4
【单选题】
近视眼的护理要点,正确的是___
A. 读书写字姿势要正确,眼与书本30cm
B. 连续看书写字2小时左右要休息或望远片刻
C. 在光线暗处及直射阳光下看书
D. 躺在床上及走路或乘车时看书
E. 连续看书写字0.5小时左右要做眼保健操
【单选题】
关子胎盘早期剥离,下列叙述正确的是___
A. 孕妇贫血程度与阴道出血量呈正比
B. 以无诱因、无痛性反复阴道流血为特点
C. 是妊娠早期的一种严重出血性并发症
D. 重型胎盘早剥孕妇的子宫硬如板状,有压痛
E. 确诊后可选择期待疗法或终止妊娠
【单选题】
下列症状与体征哪项与甲型病毒性肝炎不相关___
A. 起病发热、厌食、乏力、巩膜黄染
B. 乏力、厌食、恶心、尿色加深
C. 腹胀、肝质地硬、脾大
D. 皮肤黄染、轻度瘙痒
E. 腹软、肝大质软、轻度扣击痛
【单选题】
患者男性,50岁。因呼吸衰竭使用人工呼吸机。患者突然出现烦躁不安,皮肤潮红,大汗淋漓,浅表静脉充盈,球结膜充血水肿,此时应立即___
A. 加大氧流量
B. 增加呼吸频率
C. 检查有元气道阻塞
D. 应用呼吸兴奋剂
E. 抽血做血气分析
【单选题】
下列关于气道湿化的描述错误的是___
A. 适用痰液黏稠、不易咳出的患者
B. 温度不可过高,一般在35~37℃
C. 应尽可能延长湿化时间,以达到良好的湿化效果
D. 湿化装置应定期消毒
E. 湿化后应帮助患者及时排痰