What makes the world go round ? 

Stimulus,stimuli( plural noun) = something that stimulates = spur= something that rouses the mind or spirits or incites to activity.

Learners and students need motivation and stimuli

all the time.Then everyday , it is necessary to find

ways and activities which may improve what they

have already learned and move forward as well.

This objective of learning more , demands a certain

discipline and routine. Then if you are looking  for

good stimuli and encouragement : select materials

which you are really interested in so that you will

be able to use them as often as possible.

 It´s up to you.Good Luck !