That bison congregate in large herds suggests that they are ______ animals, yet individually they appear _______, seemingly indifferent to their circumstances.

多项选择题A notorious ______, the critic struck readers as being more concerned with the ______ of his own literary performance than with the book being reviewed.

多项选择题Many important inventions are the result of ______; for example, Chinese alchemists accidentally discovered gunpowder while trying to create ______ that would make their emperor immortal.