Would "he looked back." be considered a truncated sentence?

No it would not consider on being a full sentence.

Explanation:

1. the details that would clarify the authors purpose for writing would be after the "haley collected used soccer jersey and sent them to guatemalan children." part, he would say, "and you can also donate today to save ". so far in the text, you can see no such thing. if, near the end the author persuades you to donate to guatemalans, then you know that the author's reason to write is to persuade you.

2. what details would make the text more engaging is to see the guatemalan children's reaction to getting free jerseys.

3. the details that convey the author's attitude would be an opinion by the author, for example, if he said, "haley was a very nice girl " or, you can find the attitude by finding parts of haley's personality that he highlights. you can strengthen your tones by using more descriptive words, and simplify long sentences as much as you can.

you're welcome ; p

sir, we have done everything that could be done to avert the storm which is now coming on" is the sentence that best articulates this. then he gives the examples.   mark me brainliest