At this time, MH/CM=tan angle DCA=tanA=0.5.

When (1)H is from m to n, there is MH/CM=(2.5T)/(4-T)=0.5, and the solution is T=2/3. At this time t= 14/3s.

(2) When h is from n to m, there is MH/CM=(2-(2.5T-2))/(4-T), and the solution is T= 1, at which time t=5s.

(3) When h goes from m to n again, there is MH/CM=(2.5T-4)/(4-T), and the solution is T=2, at which time t = 6s, and p and e coincide.

(4) When P is on BE, MH/CM is always 0.5, that is, H is always on CD, and at this time, 6≤t≤8.

To sum up, when t= 14/3 or t=5 or 6≤t≤8, H falls on the CD.

I made it myself, dear. I hope to adopt. There better be a reward.