The past participle (and simple past) is earned.
The past participle is produced.
The past participle is traded.
Yes, the word 'bartering' is the present participle of the verb 'to barter'. The present participle of the verb is a gerund (a verbal noun); for example: Very few people are skilled in the art of bartering.
Barter system
The past participle of "do" is "done." The past participle of "have" is "had."
The past participle of "am not" is "have not been."
The past participle of "do" is "done."
The past tense of "have" is "had," and the past participle is also "had."
The past participle of the word "have" is "had."
The past participle of "am, are, is" is "been."
The past participle of "will" is "willed."
The past participle is thought.
The past participle of "to" is "been." The past participle of "be" is also "been."
Being is the present participle. The past participle is been.
The past tense and the past participle is "answered".
Present participle: hiding Past: hid Past participle: hidden