Explain the essential difference between the notion phoneme and the notion morpheme

Answer: Morphemes are the smallest meaningful unit in a word which can stand alone (un/event/ful; cat/s). Phonemes are the smallest unit in language phonology - / b / or / m / (bat and mat are two different words, because of different phonemes). Phonemes are combined with other phonemes to form morphemes.

Explanation:

phoneme (/ˈfoʊniːm/) is a unit of sound that distinguishes one word from another in a particular language.

For example, in most dialects of English, with the notable exception of the west midlands and the north-west of England,[1] the sound patterns / sɪn / (sin) and / sɪŋ / (sing) are two separate words that are distinguished by the substitution of one phoneme, / n/, for another phoneme, / ŋ/. Two words like this that differ in meaning through the contrast of a single phoneme form a minimal pair. If, in another language, any two sequences differing only by pronunciation of the final sounds [n] or [ŋ] are perceived as being the same in meaning, then these two sounds are interpreted as variants of a single phoneme in that language. while morpheme is the smallest meaningful unit in a language. A morpheme is not identical to a word. The main difference between them is that a morpheme sometimes does not stand alone, but a word, by definition, always stands alone. The linguistics field of study dedicated to morphemes is called morphology. When a morpheme stands by itself, it is considered as a root because it has a meaning of its own (such as the morpheme cat). When it depends on another morpheme to express an idea, it is an affix because it has a grammatical function (such as the - s in cats to indicate that it is plural).[1] Every word comprises one or more morphemes.

Not sure it seems quite difficult to me. You may want to email your teacher if nobody else replies