Final answer:
The claim that 'x' is the only letter representing multiple phonemes is false, as English has other letters like 'c', 'g', 'w', and 'y' that also represent multiple sounds depending on context.
Step-by-step explanation:
The statement that the letter x is the only letter that stands for two phonemes, /k/ and /s/, and occasionally /g/ and /z/ is false. While it is true that x often represents the sounds [ks], as in box, or [gz], as in exist, these are not the only instances where a single letter represents multiple phonemes. For example, the letter c can spell the sound [s] when followed by e, i, or y and is referred to as a soft c. On the other hand, when the letter c is followed by other letters, it typically represents the sound [k], which is referred to as a hard c. Similarly, the letter g can represent the [j] sound in certain conditions, and the letters w and y can sometimes function as vowels in English.
True. The letter x can represent the phonemes /k/ and /s/. For example, in the word 'box' it represents the /ks/ sound, and in the word 'exist' it represents the /gz/ sound. However, it's important to note that the /g/ and /z/ sounds are only occasionally represented by the letter x, specifically in words with the prefix 'ex-' and a vowel following it.