1. I just returned from a trip to Oxford on one of your coach trips.
2. I regret to say it was not an expensive, but not a pleasant one.
3. There were several defects in the service of which I can single out only three.
4. The first problem I came across was a lack of leg room when seated.
5. I am not a particularly tall man, but after only half an hour of travel, I found that I had cramps in both legs.
6. The second annoyance was the constant playing of music over the loudspeaker system.
7. Most people like to read or look out of the window quietly during their bus journey, but not when pop music is being blasted in their ears hour after hour.

I just/return/trip Oxford/one/your coach trips
 I just returned from a trip to Oxford on one of your coach trips.
I  regret/say/expensive/not/pleasant one
 I regret to say it was not an expensive, but not a pleasant one.
There/several defects/service/which/single out/only three
There were several defects in the service of which I can single out only three.
First problem/come across/lack/leg room/when/seated
 The first problem I came across was a lack of leg room when seated.
I/not/particular/tall man/but/after only/half/hour/travel/found/i/have cramp/both legs
 I am not a particularly tall man, but after only half an hour of travel, I found that I had cramps in both legs.