Rabbi Avrohom Baruch Zachariash teaches the halachas of Chol Hamoed with the Mishnah Berurah (O.C. 537:13).
0:16 Trapping rodents to protect a field.
3:45 At what point is a person guilty of cooking on Shabbos.
19:00 Bringing a flock into a field to fertilize it.
25:20 Playing pool is a grama
26:55 Using Alexa or Google to turn lights on or off