What is the most common problem of learning Mandarin as a second language?
Whilst grammar within Mandarin, compared to English, is relatively simple, the fact it is a tonal language can cause problems. Each character is pronounced with one of five different tones, each with different relative pitch changes as illustrated below: (The fifth tone is a normal, neutral tone.) The incorrect use of tone can result in characters having totally different meanings. So, getting the tones right is often the single most important thing for a new learner of Mandarin.