Fungus is singular and the plural is fungi (pronounced fun-jeye). Usually with some exceptions, the hard (g) sound as in fungus, gate, goat and gum is pronounced when the (g) is followed by a, o and u. Usually with some exceptions, the soft (g) sound as in fungi, gentle, gin and gym is pronounced when the (g) is followed by e, i, and y. If there is ever a question as to the pronunciation of a word, one can always resort to looking it up in a dictionary or just googling pronunciation of the word and listen to the pronunciation of that word. Isn’t technology great?