Here is another song to help you practice improvising. There are two bars of melody followed by two bars of backing only. You can improvise over this section. This happens three times during the song. Each two bar melody is based on several of the rhythms you have been learning.
There is also much repetition of rhythms. Repetition is important because it helps a listener to keep track and make sense of what you are singing. It also helps the other musicians you are playing with to follow you and complement what you are doing. Many of the best melodies ever written are based on the elements of repetition and variation. The 16th notes in this solo are swung. Try swinging the 16th notes in other examples you have learned.
The first version of this song is in the key of E, as shown by the key signature (four sharps). The second half contains several examples of improvisation. If you have trouble with the timing, practice the rhythm figures on one note, as in the earlier rhythm examples. Also try singing along with the recording and try to feel the timing and then imitate it.
The second version of this song is in the key of G. This version also contains improvised phrases in the second half. As with previous songs, use the version which best suits your particular vocal range.