The German letter 'c' is considered the hardest to spell for English speakers. That is due to the letter combination 'ch', which forms sounds that don't have any equivalent in the English language.
In German you'll rarely run into a 'c' that isn't followed by an 'h' except in foreign words. If that 'c' is followed by an 'ä', 'e', 'i', or 'ö', it's pronounced as a 'ts' sound (for example: circa - approximate); otherwise it's pronounced as a 'k' (for example: Creme - cream).
As already stated, the 'ch' letter combination is considered the hardest to pronounce for the English speakers; as such combination is pronounced in two different ways, neither of which exist in the English language.
When a 'ch' combination follows one of the German vowels 'a', 'o', 'u', or 'au', it's pronounced as the Scottish word 'loch'. To produce that sound, make an 'h' sound, letting the air flow out freely. While you're still producing that sound, start reducing the gap between the roof of your mouth and the back of your tongue, until friction occurs and have an audible sound.
|Buch - book||Nachthemd - nightshirt||Tochter - daughter|
|auch - also, as well||Rache - revenge||rauchen - to smoke|
The heavy 'ch' sound is produced if the 'ch' combination comes after an 'e', 'ä', 'i', 'ei', 'eu', 'äu', 'ö', or after a consonant. It's also produced when the 'ch' combination appears at the start of a word. To pronounce it, try saying the word 'human', but draw out the 'h' sound longer than you usually do. If you could do that, then you should have very little trouble pronouncing the guttural 'ch' sound.
|manchmal - sometimes||ich - I||leuchten - to shine|
|leicht - light||Lächeln - smile||köchin - cook|
|'Ch' at the start of a word|
|Chef - chief||Chemie - chemistry||China - China|
The German 'chs' letter combination is simply pronounced as a 'ks', similar to the English word 'blocks'.
|'Chs' letter combination|
|Achsel - shoulder||sechs - six||nächst - next to|
The German 'ck' letter combination is pronounced as the English 'k'. English speakers might find it hard to differentiate between the 'ch' and the 'ck' letter combinations at first, but it becomes much easier by time.
|'Ck' letter combination|
|Händedruck - handshake||lockig - curly||backen - to bake|
|nackt - naked||ticken - to tick||zurück - back|
Fortunately, there aren't any more combinations involving the German letter 'c'. However, you should revise this lesson more than once; as the 'c' letter is used in extremely many German words, and with many different and difficult variations.