没有第一个 console.log 的原因是因为 length 属性有拼写错误。您使用的 lenght 是无效的。

没有第二个 console.log 的原因是因为有一个 unnecessaryWords 数组，因此您需要使用 indexOf() （或 includes() ）来检查这些单词是否存在于该数组中：

let story = 'Last weekend, I took literally the most beautiful bike ride of my life. The route is called "The 9W to Nyack" and it actually stretches all the way from Riverside Park in Manhattan to South Nyack, New Jersey. It\'s really an adventure from beginning to end! It is a 48 mile loop and it basically took me an entire day. I stopped at Riverbank State Park to take some extremely artsy photos. It was a short stop, though, because I had a really long way left to go. After a quick photo op at the very popular Little Red Lighthouse, I began my trek across the George Washington Bridge into New Jersey.  The GW is actually very long - 4,760 feet! I was already very tired by the time I got to the other side.  An hour later, I reached Greenbrook Nature Sanctuary, an extremely beautiful park along the coast of the Hudson.  Something that was very surprising to me was that near the end of the route you actually cross back into New York! At this point, you are very close to the end.';

let overusedWords = ['really', 'very', 'basically'];

let unnecessaryWords = ['extremely', 'literally', 'actually'];

const storyWords = story.split(' ');

console.log(storyWords.length);


const betterWords = storyWords.filter(word => {
  return unnecessaryWords.indexOf(word) === -1;
});

console.log(betterWords);

您可以执行以下操作：

let story = 'Last weekend, I took literally the most beautiful bike ride of my life. The route is called "The 9W to Nyack" and it actually stretches all the way from Riverside Park in Manhattan to South Nyack, New Jersey. It\'s really an adventure from beginning to end! It is a 48 mile loop and it basically took me an entire day. I stopped at Riverbank State Park to take some extremely artsy photos. It was a short stop, though, because I had a really long way left to go. After a quick photo op at the very popular Little Red Lighthouse, I began my trek across the George Washington Bridge into New Jersey.  The GW is actually very long - 4,760 feet! I was already very tired by the time I got to the other side.  An hour later, I reached Greenbrook Nature Sanctuary, an extremely beautiful park along the coast of the Hudson.  Something that was very surprising to me was that near the end of the route you actually cross back into New York! At this point, you are very close to the end.';

let overusedWords = ['really', 'very', 'basically'];

let unnecessaryWords = ['extremely', 'literally', 'actually' ];

const storyWords = story.split(' ');

console.log(storyWords.length); // length spelling mistake


const betterWords = storyWords.filter(word=>{
  if (unnecessaryWords.includes(word)){ // check words in the array like that
    return false;
  }
  else {
    return true;
  }
});

console.log(betterWords);

请尝试以下操作：

这是storyWords.length而不是lenght；

let story = 'Last weekend, I took literally the most beautiful bike ride of my life. The route is called "The 9W to Nyack" and it actually stretches all the way from Riverside Park in Manhattan to South Nyack, New Jersey. It\'s really an adventure from beginning to end! It is a 48 mile loop and it basically took me an entire day. I stopped at Riverbank State Park to take some extremely artsy photos. It was a short stop, though, because I had a really long way left to go. After a quick photo op at the very popular Little Red Lighthouse, I began my trek across the George Washington Bridge into New Jersey.  The GW is actually very long - 4,760 feet! I was already very tired by the time I got to the other side.  An hour later, I reached Greenbrook Nature Sanctuary, an extremely beautiful park along the coast of the Hudson.  Something that was very surprising to me was that near the end of the route you actually cross back into New York! At this point, you are very close to the end.';


var storyWords = story.split(' ');

console.log(storyWords.length) // not lenght;


function betterWords(storyWords) {
  foreach(var word in storyWords) {
    if (word === unnecessaryWords) {
      return false;
    } else {
      return true;
    }
  }
}

console.log(betterWords(story));