English spelling is quite confusing for most of my clients. Today during a session, a client read the word SHOE as S-H-EW. Seeing two letters, S and H, it makes sense that it would be spoken/read S+H. However, this is not the case. When the letters SH are together in a word, we read and pronounce them as ONE sound, SH. To make the SH sound, pucker your lips and blow. This is quite different than saying S+H. For that sound combination the lips would smile then relax.
There are other two letter combinations like SH. Read about them here.