You could always define what you mean by "things" give examples etc. If you are reffering to an object you could say item instead. If you are reffering to a task you could use the words tasks, activity, goals etc.
Explanation:
A good way for replacing words is looking up synonyms :)
Juliet worries that the poison will kill her instead of put her to sleep, and Friar Lawrence is attempting to kill her for being sinful. She also worries that she will wake up before Romeo comes to save her, or she will die of suffocation because there is no fresh air in the tomb.
