What you'll learn

• Mấy vs bao nhiêu for 'how many'
  Both ask about quantity. Use mấy when you expect a small number (about 10 or fewer), and bao nhiêu for larger or unknown amounts, like prices.
  Một trái xoài bao nhiêu tiền? : How much does one mango cost?
• Yes/no questions with có ... không?
  To make a yes/no question, put có before the verb or adjective and không at the end. Answer with 'Có' for yes or 'Không' for no.
  Anh có khỏe không? : Are you well?
• Counting with classifiers
  Vietnamese does not add plural endings. When you count, put a classifier between the number and the noun: cái for objects, con for animals, trái for fruit, người for people.
  Tôi mua hai trái xoài. : I buy two mangoes.