text: /*******************************************************************************
  Write a function bigramArray(sentence) that takes in a sentence string and returns
  the an array of containing all bigrams in the sentence. A bigram is a pair of
  consecutive words of a sentence.
  
  Examples:
  
  bigramArray('today is a great day') => [ 'today is', 'is a', 'a great', 'great day' ]
  bigramArray('bigrams are very useful') => [ 'bigrams are', 'are very', 'very useful' ]
  *******************************************************************************/
  
  function bigramArray(sentence) {
    var bigrams = [];
    var words = sentence.split(' ');
  
    for (var i = 0; i < words.length - 1; i++) {
      var word1 = words[i];
      var word2 = words[i + 1];
      var bigram = word1 + ' ' + word2;
      bigrams.push(bigram);
    }
  
    return bigrams;
  }
  
  /**************DO NOT MODIFY ANYTHING UNDER THIS  LINE*************************/
  module.exports = bigramArray;
  