You may be quite good at writing English, and even fairly reliable when it comes to reading. However, when you actually talk to native English speakers, you find that they are always asking you to repeat yourself, and you may not get through to them at all. The problem is the way you speak the language. You are having problems with pronunciation.
This is a series of books that teaches English pronunciation [PRO-NUN-SEE-AYSH'N] (the way to speak the language) through various simple topics. It is aimed at non-native speakers of English who wish to improve their pronunciation of the language. This series is intended particularly for native speakers of the Chinese languages, and their particular problems with spoken English.
The book doesn't use strange symbols and letters, and no technical terms, but ordinary English letters and sounds.
It assumes some proficiency with simple written English, perhaps to the British GCSE Level C standard.
This particular edition teaches spoken English through the topic of numbers and simple sums.