This is called the three four time signature.
It tells you there are three beats in each bar.
Three four time is also known as waltz time.
Count 1 2 3, 1 2 3 as you play this song.
A dot after a half note means that you hold the note for three beats.
Once again, sing the words as you play this song and try walking in time as you sing and play. Remember that you will be counting 1 2 3, 1 2 3. This means that on the first beat of one bar your right foot will be hitting the floor and on the first beat of the next bar, your left foot will be hitting the floor.