A with Easy Consonants. The pinyin vowel a has a rather uniform pronunciation in Chinese, very similar to the "a" sound in the English "father". (The two exceptions to this pronunciation rule are ian and üan, both covered in later sections.) ... The vowel a can also combine with other vowels in a single syllable.
Mandarin Chinese is a tonal language. In order to differentiate meaning, the same syllable can be pronounced with different tones. Mandarin's tones give it a very distinctive quality, but the tones can also be a source of miscommunication if not given due attention.