有没有哪位大佬帮忙看看我理解得对不对

so what?In the first picture, “juxtapose” means contrast, compare, etc. not something like “backdrop”.You only have one example and I can’t understand why you said “set off” at first, many dictionaries tend to explain one word by using another word, such as numerous, it means “many” in longman dictionary, so numerous and many are the same word?I can’t understand your thought.