can anybody suggest me some yoga exercises to reduce my tummy .?

I do yoga and it works great. Go to google and press in yoga poses. Or you can get a book from the library.
Yoga Poses w/ Sonja 6, Anxiety & Stress Workout Fitness Routine, Yoga for Beginners

One of the best way to learn fitness exercises for pregnant woman is by pregnancy fitness videos. It helps you to get an easier birth and shows you the way to stay healthier during pregnancy days. These pregnancy fitness videos are a product by many health professionals.
You can select from various types of pregnancy [...]