【多选题】【消耗次数：1】
设函数f: Z?N, f(x)=|x|，则它是：
①
满射;
②
单射;
③
双射;
④
函数.
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随机题目
【单选题】
What role does a teacher play in the following activity? The teacher asks students to produce conversations (either orally or in writing) by using particular patterns or expressions they have just learned.
①
Controller
②
Assessor
③
Organizer
④
Prompter.
【单选题】
What role does a teacher play in the following activity? When students are doing a group-work task, the teacher joins one or two groups for a short period of time.
①
Controller
②
Assessor
③
participant
④
Resource-provider.
【单选题】
What role does a teacher play in the following activity? The teacher has a word in his mind and asks students to guess by asking only Yes/No questions until they make the correct guess.
①
Controller
②
Assessor
③
participant
④
Resource-provider.
【单选题】
Which of the following is the advantage of pair work?
①
It is an ideal way to show materials and do presentations together
②
It allows students to work together rather than under teacher’s guidance
③
It reinforces a sense of belonging among a group of members
④
It is very stressful.
【单选题】
Which of the following is the time when students work in a pair?
①
When all the students are under the control of the teacher
②
When students work in pairs on an exercise or a task
③
When students work in small groups
④
When students are expected to work on their own at their own speed.
【单选题】
What role does a teacher play in the following activity? The teacher writes one of five numbers (1-5) on a number of cards (the same number as the students). Each student draws one card. Those who have drawn number 1 will form group1, and those who have drawn number 2 will form group 2. Thus the students are put into five groups in a random way.
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Controller
②
Assessor
③
Organizer
④
Prompter.
【单选题】
What are language contents?
①
Structures, vocabulary, functions and topics
②
Pictures, vocabulary, communication and topics
③
PPT, structures, aims and summary
④
Structures, aims, functions and topics.
【单选题】
Which part is to be finished after a lesson in a lesson plan?
①
Teaching aids
②
End of a lesson summary
③
Optional activities and assignment
④
After lesson reflection.
【单选题】
What are the principles for good lesson planning?
①
Aim, variety, flexibility, learnability and linkage
②
Aim, preparation flexibility and linkage
③
Aim, micro-planning, macro-planning and flexibility
④
Aim, micro-planning, macro-planning and variety.
【单选题】
What is the function of optional activities?
①
Backups in case the lesson goes too fast and there are a few minutes left
②
Prepared for good students
③
Prepared for bad students
④
Used for emergency.