2. threshold   noun   

原句: Video and computer games offer "threshold effects," where prizes or level changes are dribbled out to keep us hooked.

意思:
a. the floor or ground at the bottom of a  doorway , considered as the entrance to a building or room
b. the level at which sth starts to happen or have an effect
c. the point just before a new situation, period of life, etc. begins

字源: Old English therscold, threscold; related to German dialect Drischaufel; the first element is related to thresh (in a Germanic sense ‘tread’), but the origin of the second element is unknown. 

例句:
a. She stood hesitating on the threshold.
b. He has a low  boredom threshold.
c. She felt as though she was  on the threshold of  a new life.



3. novice   noun   

原句: Instead, students are rated at levels from novice to master.

意思: a person who is new and has little experience in a skill, job or situation

字源: Middle English: from Old French, from late Latin novicius, from novus ‘new’. 

例句: I'm a complete novice at skiing.



4. intuitive   adjective   

原句: He was struck by the fact that games are often long and demaning yet designed to be so intuitive that no manual is ever needed.

意思: obtained by using your feelings rather than by considering the facts

字源: late 15th cent. (originally used of sight, in the sense ‘accurate, unerring’): from medieval Latin intuitivus, from Latin intueri ‘consider’, from in- ‘upon’ + tueri ‘to look’. 

例句: He had an intuitive sense of what the reader wanted.



5. retention   noun   

原句: If visuals accompany an oral presentation, retention rises to 30 percent.

意思: the ability to remember things

字源: late Middle English (denoting the power to retain something): from Old French, from Latin retentio(n-), from retinere ‘hold back’, from re- ‘back’ + tenere ‘hold’. 

例句: Visual material aids the retention of information.