ARE - Second-person singular simple present tense of be.
ART - Human effort to imitate, supplement, alter, or counteract the work of nature.
EAR - The organ of hearing, consisting of the pinna, auditory canal, eardrum, malleus, incus, stapes and cochlea.
ERA - A time period of indeterminate length, generally more than one year.
LET - To allow to, not to prevent (+ infinitive, but usually without to).
RAT - A medium-sized rodent belonging to the genus Rattus.
TAR - A black, oily, sticky, viscous substance, consisting mainly of hydrocarbons derived from organic materials such as wood, peat, or coal.
EARL - A British nobleman next in rank above a viscount and below a marquess; equivalent to a European count. A female using the style is termed a countess.
LATE - Near the end of a period of time.
RATE - A wage calculated in relation to a unit of time.
REAL - A commodity; see reality.
TALE - Number.
TART - Sharp to the taste; acid; sour.
TEAR - To rend (a solid material) by holding or restraining in two places and pulling apart, whether intentionally or not; to destroy or separate.
ALERT - Attentive; awake; on-guard.
ALTER - To change the form or structure of.
LATER - Comparative form of late: more late.
TREAT - An entertainment, outing, or other indulgence provided by someone for the enjoyment of others.
LATTER - Relating to or being the second of two items.
RATTLE - A sound made by loose objects shaking or vibrating against one another.