Plurals (nouns of foreign origin)

Singular - Plural

cactus-cacti
fungus – fungi / funguses
radius – radii
stimulus – stimuli

axis-axes
analysis – analyses
basis – bases
crisis – crises
diagnosis – diagnoses
hypothesis – hypotheses
oasis – oases
thesis – theses

bacterium – bacteria
criterion – criteria
curriculum – curricula / curriculums
datum – data
medium – media
phenomenon – phenomena
antenna – antennae
formula – formulae / formulas