input: Write a function to generate a list of lists of words from a given list of strings, where each sublist starts with the first word of the respective string followed by the following words of that string. If the list of strings is empty, return an empty list.
  assert get_word_lists(["Hello world", "This is a test"])==[["Hello", "world"], ["This", "is", "a", "test"]]
  assert get_word_lists(["First second", "One two three"])==[["First", "second"], ["One", "two", "three"]]
  assert get_word_lists([""])==[[""]]
  assert get_word_lists([])==[]
  assert get_word_lists(["SingleWord"])==[["SingleWord"]]
  assert get_word_lists(["Multiple words in one string"])==[["Multiple", "words", "in", "one", "string"]]
output: def get_word_lists(strings):
      return [[word for word in s.split()] for s in strings]