In a little grassy bay between tall clumps of Mediterranean heather, two children, a little boy of about seven and a little girl who might have been a year older, were playing, very gravely and with all the focussed attention of scientists intent on a labour of discovery, a rudimentary sexual game.
There are no more uses of "rudimentary" in the book.
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NEWLY ZEN thanks to Yoga Janet, well fed by Pop, and now proficient in concrete-mixing as well as rudimentary electrical work, I felt as if I were making the most of this prison thing.
Piper Kerman -- Orange Is the New Black
Ootek had been taught a few words of English by Mike, and his perceptivity was so excellent that we were soon able to establish rudimentary communications.