Sure! Here’s a rewritten version of the sentences you provided:

27. If you don't watch the program, you can't really judge.
=> My mother would disagree unless…

28. John and Mary relocated to Edinburgh twenty years ago.
=> It has been twenty years since John and Mary moved to Edinburgh.

29. Despite working hard, she never seems to succeed.
=> She works hard; however, she never seems to succeed.

30. Flying is significantly more costly than traveling by train.
=> Traveling by train is less expensive than traveling by plane.

31. They took a considerable amount of time to decide to marry.
=> It took them a long time to make the decision to get married.

32. Reaching the art gallery is straightforward.
=> It is easy to get to the art gallery.

33. My friend and I enjoy chatting on Facebook.
=> My friend and I are interested in chatting on Facebook.

34. The town was closer than we anticipated.
=> The town wasn’t as far away as we thought.