In the piece below, the time-signature is 4/4. That means that there are 4 beats in a bar (top number) and that a quarter-note/crotchet lasts for one beat (bottom number). The underlying count will therefore be **1** - 2 - 3 - 4 - **1** - 2 - 3 - 4 etc., with a stress on each 'one'.

Each of the 4 bars is filled with quarter-notes (crotchets). They're all 'A's and they all last for one beat, so -

Count : **1** - 2 - 3 - 4 - **1** - 2 - 3 - 4 etc. and play a new A with each count.