To look for common writing problems.
You did not provide the excerpt but in the end Jekyll was not able to permanently resist. It was implied that he was actually Hyde deep inside and that Hyde is the one who will overtake and he won't be able to come out again. In the end he dies as Hyde and people find out what happened out of letters that he sent while he was sane.
Answer:
1) what he was doing.
2) that he would come.
3) If i could help her.
4) that honestly is the best policy.
5) That I would get the first prize.
6) Why he is late?.
7) What he wants.
8) What I am going to say.
9) That she should forget me so quickly.
10) That you should behave like this.
I HOPE THIS HELP! :)