Giới Thiệu Về Hà Nội Bằng Tiếng Anh Đơn Giản, Cực Hay ... · Ha Noi has a lot of green trees, parks, lakes, Which are lungs of the thành phố, keep the air clean & fresh. However, Ha Noi has problems with traffic và pollution. Only over 6 million people but there are 4.5 million motorxe đạp and car. Traffic jams occur. There''s a lot of smoke & dust in the air. So the air isn''t really clean.