Thank you very much for your help.
Here are some more sentences I'm doubtful about.
1) Being a Renaissance man, Hamlet doubts the existence of an afterlife.
2) He doubts suicide/ He has doubts about committing suicide/ He is doubtful about suicide. He is not sure of what will happen after death. Every man (better: Everyone one/each of us) is scared of what will happen after death.
3) The hero usually has (goes through is also OK?) a period of doubt in which (during which) he projects (correction: plans) his revenge.
4) Hamlet is a revenge tragedy because it includes (not respects) all the features of the revenge tragedy present in Seneca.
5) Hamlet decides to have vengeance for (?) his father’s murder.He seeks revenge for his father’s murder. He wants to take revenge on Claudius for/revenge himself for /avenge his father’s murder.
6) Hamlet wants his revenge murdering the killer of his father. Better: Hamlet wants to take his revenge by killing Claudius, his father’s murderer.
1 answer
2) He has doubts about committing suicide. He is not sure what will happen after death. Most people are unsure of what will happen after death. <~~(I wouldn't say "everyone" in the last sentence, since you cannot prove that every single person on earth is unsure or scared of what happens after death.)
3) The hero usually goes through a period of doubt during which he plans his revenge.
4) Hamlet is a revenge tragedy because it includes all the features of the revenge tragedy present in Seneca. <~~(You should make clear the reference to Seneca. Are you referring to a particular work of his in which he analyzes drama?)
5) Hamlet decides to take vengeance for his father’s murder. He seeks revenge for his father’s murder. He wants to take revenge on Claudius to avenge his father’s murder.
6) Hamlet wants his revenge by murdering the killer of his father. Better: Hamlet wants to take his revenge by killing Claudius, his father’s murderer. Yes, the second sentence is better.