The word, “Base”, and it’s various transformation is the first example of what I call, “Unique Word-Transformation” TOEFL Vocabulary. For more of a thorough description about that and the other classifications of TOEFL Vocabulary, you can read the blog post I wrote on that subject here.
As you can see the different forms of these words, all have a common element, and that is the “foundation”, “starting point”, or “elementary” principle. However, the way that they can be used in sentences varies a bit from one word form to the next.
And though the root form “Base” may or may not show up on the exam, the other forms could very-well be in and of the Reading Passages or Listening Section recordings, or can be used in the reading or listening portions of any of the Speaking or Writing Sections of the exam – and most certainly can be used in one’s answers in the Speaking or Writing Sections of The TOEFL iBT Exam.
Therefore, I highly suggest clicking on the words above to find out their proper pronunciation and to follow the links to there pages on Wiktionary.org to explore some of the other definitions as well.
… And I’ll “see” you all again soon.
Have An Excellent Day!