An "iamb" is a word or set of words that goes 'da-DAH', like "my KNEE", or "your FACE", or "his DOG", or "come HERE".
Many poems have the same rhythm (beat) in each line, and there are different rhythms they can have. I can show you that, if I take a poem you know, and recite it first with the correct beat, and then with the wrong beat.
Here's the correct beat: MAH-ree HAD a LIT-tle LAMB its FLEECE was WHITE as SNOW.
For the wrong beat, let's use 'iambs' like I explained up above: ma-REE had A lit-TLE lamb ITS fleece WAS white AS snow.
If a poem is in the rhythm of "iambic tetrameter", then each line is made out iambs, and there are 4 of them ("tetra") in each line.
Now I have to try and find an example for you. Thank you very much.
I'll make one up. Remember, an iamb goes 'da-DAH":
my DOG came IN-to SCHOOL one DAY and CHASED the HAM-sters ALL a-ROUND. the PRIN-ci-PLE came IN-to CLASS and TOOK my DOG down TO the POUND.
Listening to music triggers the areas of the brain that have to do with spatial reasoning. Music can even alter the brain if it is studied from a young age. Research shows that musical training in children can improve the activity of important neural systems.