Englishfor English speakers
imperfect
—
adjective
not perfect; defective or inadequate
had only an imperfect understanding of his responsibilities
imperfect mortals
drainage here is imperfect
—
adjective
(= fallible, frail)
wanting in moral strength, courage, or will; having the attributes of man as opposed to e.g. divine beings
I'm only a fallible human
frail humanity
—
noun
(= progressive)
a tense of verbs used in describing action that is on-going
obligation
Noun
—
An obligation is a duty, something you must do.