The Beast and the False Prophet of Revelation are "She's"
Yep, that's right, according to my Bible, the Beast is a she, and so is the second Beast, her false prophet.
--at least according to my French Bible (I've just about read through the French NT as part of my prepatory studies for my PhD).
In French, the word for beast is bete (often the "st" sound in English is found simply as a "t" sound in French). Bete is a feminine noun. In English, we generally don't assign gender to nouns like they do in French, Spanish, most other Romance languages, Greek and Hebrew, etc. In English, "book," for example, is an "it," but in French "book" is a "he."
This scrambles up our translations sometimes, as it does with reference to the two Beasts in Revelation.
In Greek, the noun "beast" (therion) is neuter, and is usually referred to as "it." However, the two Beasts of Revelation are personal entitities. Consequently, our English versions are quick to use personal masculine pronouns for them (he, his, him). This is quite natural, and is similar to what we do in regard to the Holy Spirit which, in Greek, is neuter (it, its).
However, in French, since beast (bete) is feminine, it would be quite a slaughtering of the language to assign masculine pronouns to the Beast. Consequently, in the French translation, "she" had seven heads, and no one was able to make war with "her," and "she" spoke blasphemies.
So, this raises the issue of the translator having to be a slave to two masters. The first master is the Greek, which would require the English translator to use neuter pronouns for the Beast: "It" spoke blasphemies; "it" had seven heads, etc. But this conveys to the reader that the Beast was a non-personal entity, when clearly it was a thinking, feeling, acting being worthy of a personal, not impersonal, pronoun.
The second master to which the translator must be a slave is the receptor language, for example, English. To make sense to English readers, the translator ought to use the personal pronoun--either the masculine or the feminine would be justifiable. (Here is a clear case of our male-bias getting the best of us.) However, this is in conflict with the Greek master, for the Greek does not assign gender to the Beast.
All this is true also for French.
In most passages, NIV and NRSV try to please both masters equally. ESV, NASU, RSV, all try to give precedence to the Greek master. NLT tries to give precedence to the English master.
Sometimes, it's a hard task to try to serve two masters, but in translation theory, you really need to.