Hi, i will use a plane to Harbin at 26-29 of May.

Hello, you have enough time to cover these spots.
One day is worth ina nd near the Zhongyang/Central Street. Take airport shuttle bus line 3 to reach directly. Then have fun with shopping and dining, and in the St. Sophia Cathedral. If there is time left, go to Zhaolin Park.

May 27: Sun Island - Siberian Tiger Park （take bus no. 29 to travel between）
May 28: Volga Manor (take a taxi there from city proper or take bus no. 377 to Chenggaozhenzi and then transfer to no. 340 to reach)
May 29: Polarland - Stalin Park (city bus no. 126 or take a taxi)

In this way, you can make full use of your time. If you have further demands, just let me know.

Thank you for helping me..

Do you have any recomended place again? Yes, actually i have so many time to going somewhere there. Please let me know and the of course the transportation to go there.
In day 3, i have a plan to booked a hotel near volga manor, do you have recomendation hotel and how much /night.
Thank you very much..

Apart from the places mentioned above, you can go to Polarland. It is adjacent to Sun Island Park. You can take a taxi to reach it.

For accommodation, you can consider the Volga Manor Hotel in Minqiang Village, Chenggaozi Town. It costs CNY 200-600 per night. You can dial at 86-0451-55156801 to book a room.