Thank you, goldentone!Ganymed, I start trilling on D, then resolve it with B-C-D-E-G.Someone else would be better at answering about 'rules'. I would in this case try different trills. Try starting on C. Try on D. Change speeds, fast or slow. The least amount of trilling I can think of would be C-D-C-B-C-D-E-G. Do it according to your present ability!
Thannks for helping me one more question. Do you play the B and C as a grace note for the D E`?