examples are ‘b’ in ‘lamb’ (most dialects of english); ‘gh’ in ‘through’; ‘p’ in ‘psychiatry’.

but your question is strangely phrased. i am not sure that this is the answer being looked for.

….

marlowe’s ‘passionate shepherd’ and raleigh’s bitter riposte to it (raleigh and marlowe seem to have known each other well) are not sonnets (in the modern sense) since they do not have fourteen lines. they are pastoral ballads.

interestingly they could have been called sonnets at the time, when the term sonnet had a much broader meaning; but not in modern english usage.

2. The Passionate Shepherd is an example of a pastoral poem written in iambic tetrameter. Since the poem has more than 14 lines, technically it is not a sonnet.