Originally Posted by: axe2can anyone pls explain to me how many strums there are in eight notes and sixteen notes ect.i should know this already but I don't.[/quote]
Eighth notes means that a measure of 4 beats has been split into 8 equal parts. A complete pattern of eighth notes is counted like this.

1-and-2-and-3-and-4-and

Sixteenth notes means that a measure of 4 beats has been split into 16 equal parts. A complete pattern of sixteenth notes is counted like this.

1-e-and-a-2-e-and-a-3-e-and-a-4-e-and-a

The numbers (1, 2, 3, 4) are the downbeat counts of the measure, of time passing.

Look at the notation graphic on this page.

http://www.guitartricks.com/lesson.php?input=10274
[QUOTE=axe2]
on sixteen notes does that mean u strum sixteen times one down one up.

The number of eighth or sixteenth notes in a measure of music does not automatically tell you or translate into a up or down strumming patterns. That is something separate you have to figure out based on how the music sounds or the ease of playing it.

Quite often a strumming part can easily be turned into a pattern of alternating up & down. For example, in a steady eighth note pattern you'd have a down strum on every downbeat & an up strum on every upbeat:

1-down
and-up
2-down
and-up
3-down
and-up
4-down
and-up

But you could just play them all with down strums. There is no guarantee either of these will automatically work for any given song.

Rhythmic subdivisions are covered in detail in GF2 chapter 4 starting here.

http://www.guitartricks.com/lesson.php?input=10272

Have a look through that tutorial & see if it helps. Best of success!