if i am in beijing how to go terrakota? and how to go temple of heaven?

Tiananmen Square can be reached by Beijing subway line 1 and you can get off at Tiananmen East or Tiananmen West to walk there then. The Gugong - Forbidden City, is within walking distance from the square. To go to the Temple of Heaven, you can use local subway line 5 to get off at Tiantandongmen station, which is close to the east gate of the attraction.

As for Great Wall, I wonder which section you would like to visit. If for Badaling section, local subway line 2 can take you to Xizhimen, from where u can easily walk to Beijing North Train Station. There you can take a direct bus to reach. For Mutianyu, go to Dongzhimen first and then at Dongzhimen Outer, take Tourism Bus no. 867 to reach!

By mentioning "tarrakota", you must refer to the Terracotta Warriors Museum in Xian. Well, you can take a high speed train at Beijing West Train Station to Xian North. Upon arrival, buy the entrance ticket of the museum at the underground of the train statio and then you can take the free shuttle bus to get to the scenic spot for a good visit!

After that, take the free shuttle bus back to Xian North to catch a high speed train to Luoyang Longmen to have fun!

May everything be clear here!