To form the passé composé of verbs using avoir, conjugate avoir in the present tense (j'ai, tu as, il a, nous avons, vous avez, ils ont) and add the past participle of the verb expressing the action. Put the words together this way: subject + helping verb (usually avoir) + past participle
Copper is best for conducting electricity. it is more efficient than any other electrical conductor because of its superior conductivity.
On parle francais en cambodie, Laos, et vietnam