What is the principal part of the underlined verb in the sentence?
our neighbors recently installed a new outdoor lighting system.
a.
present
b.
present participle
c.
past
d.
past participle

What is implied in this sentence from mark twain's "the £1,000,000 bank-note"? i was puzzled, and wanted to discuss the matter a little further, but they didn't; so i took my leave, feeling hurt and insulted to be made the butt of what was apparently some kind of a practical joke, and yet obliged to put up with it, not being in circumstances to resent affronts from rich and strong folk.