As for a lesson plan,a teacher says,"When do lesson planning,I always prepare some extra?and alternative tasks and activities so that I have the options to cope with the unexpected situations."According to the teacher′s words,we can know that the teacher follows the principle of__________in?lesson planning.
A.linkageB.varietyC.flexibilityD.learnability

The need for sleep varies__________from person to person.
A.conservativelyB.alternativelyC.considerablyD.influentially

In English teaching,teachers should NOT pay attention to__________.
A.providing independent learning and communicating opportunities for studentsB.correcting students'mistakes and errors in the process of learning immediatelyC.encouraging students to discuss,cooperate,experience,practice,and explore the way to?master EnglishD.cultivating students'interest

Children may get into some bad habits__________they lack self-discipline.
A.whenB.unlessC.thoughD.until,

Out of pity,I offered to help the old man up,but he__________smilingly.
A.rejectedB.declinedC.refusedD.denied

I have kept the portrait__________I can see it every day as it always reminds me of my?university days.
A.whichB.whereC.whetherD.when