Представленные ниже слова написать во множественном числе на английском языке:
radius, crisis, antenna, appendix, criterion, stimulus, encyclopedia, prognosis, sanatorium, axis, aircraft, medium, matrix, nebula, phasis, optimum, syllabus, supernova, synthesis, spectrum, thesis, equipment, maximum, hypothesis, equilibrium, millennium, oasis, curriculum, phenomenon, analysis, alumna, alumnus, bureau, half, human being, person, atrium, experience, spa, issue, research, «how and why», «do and don't», literatus, tenet.

radiuses, crisises, antennas, appendixes, criterions, stimuluses, enceclopedias, prognosises, sanatoriums, axises, aircraftes, mediumes, matrixes, nebulas, phasises, optimumes, syllabuses, supernovas, synthesises, spectrumes, thesises, equipmentes, maximumes, hypothesises, equilibriumes, millenniumes, oasises, cirriculumes, phonemonones, analysises, alimnas, alumnas, alumnuses, bureaus, halfs, humans being, personas, atriumes, experiences, spas, issies, researches, how and why (wtf? этот вопрос не поставить во множественное число как и сл. предложение.), do and don't, literatus, tenetes.