answer:I sat captivated throughout… ...was left with more questions rather than answers, but in a good way. Although I have always been… no comma ...how time was not constant but depend depending on an object’s speed. ...and watching related videos on YouTube, I have a better understanding (now), even though I have not mastered the idea. added now(?) and a comma ...which is seems to be evidence… ...come to the conclusion that time travel is not possible… ...it’s just that the conditions to make it happen is are hard to accommodate. Space-time is curved like a cylinder*;* the top of the cylinder is the same as the bottom*,* a wormhole is a tunnel that goes through the cylinder that leaves you where you started*,* only older. (I’ve added a ; and two commas) Not sure if that last sentence is very fluent; you might want to redo that one? These ‘improvements’ are done by an ESL speaker, so don’t take them for granted, please. I am sure better advice will come along :-)