It would be important for a firefighter to know another language because he could have to save someone who doesn't speak English
The likely connotation of the underlined words might be <em>Nwoye is depressed at the news of Ikemefuna’s death, but he accepts all the custom of his clan.</em>
We can assume this because it seems that although he is sad because of the death, he felt inside like he has to deal with it and carry on, owing to the fact that are traditions that he has to respect. This can be considered as a metaphor when is using the tightened bow.
Well, I need more detail but my guess i would have to say. "Jump"
