The present participle of build is building. This word also means a large structure, but in this instance, it means to be in the process of trying to build something.
Being is the present participle. The past participle is been.
Getting is the present participle of get.
The present participle is doing.
Presenting is the present participle of present.
Presenting is the present participle of present.
The present participle is choosing.
The present participle is walking.
The present participle is cleaning.
The present participle is seeking.
The present participle of "understand" is "understanding."
The present participle is putting.
The present participle is leading.