input: Write a function to generate a list of lists of words from a list of strings. Each sublist should contain the first word of each string, then the following words of each string. If the input list of strings is empty, return an empty list.
  
  def get_word_lists(strings):
      if not strings:
          return []
      word_lists = []
      for string in strings:
          words = string.split(" ")
          word_lists.append([words[0], *words[1:]])
      return word_lists
  
  assert get_word_lists(["Hello world", "This is a test"])==[["Hello", "world"], ["This", "is", "a", "test"]]
  assert get_word_lists([])==[]
output: def get_word_lists(strings):
      if not strings:
          return []
      word_lists = []
      for string in strings:
          words = string.split(" ")
          word_lists.append([words[0], *words[1:]])
      return word_lists