I still have some more sentences I need to check. Can you please have a look at them, too?

1) Hamlet arranges a play at court in order to expose his father's murdere.
So in the third act there is the-play-within-the play that is paradoxically the only true thing in the play.
2) Hamlet considers death from two points of view: the Medieval perspective, which considers death as physical liberation from the body is countered by the Renaissance one, which doubts the existence of an afterlife.
3) You shouldn't write a list of themes but express them into a cohesive paragraph using appropriate sentence connectors.
4) The ghost wants Hamlet to avenge him (better: his murder) by killing his brother Claudius.
5) The ghost appearance: correction the appearance of a ghost.
a revenge plan or a plan of revenge

1) Hamlet arranges a play at court in order to expose his father's murdere.

So in the third act there is the-play-within-the play that is paradoxically the only true thing in the play.
It's not a good idea to start sentences with "So" -- that word is a conjunction, and the sentence needs to be connected to the sentence before it.

Check spelling.

It should be "play-within-a-play" (not "the" and one more hyphen).

I'm not clear on what you mean by "the only true thing."


2) Hamlet considers death from two points of view: the Medieval perspective, which considers death to be liberation of the soul from the body, countered by the Renaissance view, which doubts the existence of an afterlife.

3) You shouldn't write a list of themes but express them in a cohesive paragraph using appropriate sentence connectors.

4) The ghost wants Hamlet to avenge his murder by killing his brother Claudius.

5) The ghost appearance: correction the appearance of a ghost. <~~OK
a revenge plan or a plan of revenge
better: a plan to avenge OR a plan to seek revenge (Remember that "avenge" is a verb and "revenge" is a noun.)

Sure, I can help you check the sentences and make any necessary corrections or improvements. Here are the revised versions:

1) Hamlet arranges a play at court in order to expose his father's murderer. In the third act, there is a play-within-the-play that paradoxically becomes the only true aspect of the entire play.

2) Hamlet contemplates death from two different perspectives: the Medieval viewpoint, which sees death as a physical liberation from the body, is contrasted with the Renaissance perspective, which questions the existence of an afterlife.

3) Instead of writing a list of themes, it is better to express them in a cohesive paragraph using appropriate sentence connectors.

4) The ghost wants Hamlet to avenge his murder by killing his brother Claudius.

5) The correct phrasing is "the appearance of a ghost." Regarding the last part, it would be more accurate to say "a revenge plan" rather than "a plan of revenge."

Please let me know if you have any further questions or need additional assistance!