Constructs a sentence part object.

@param {string} sentencePartText The text in the sentence part.
@param {Array} auxiliaries The list of auxiliaries from the sentence part.
@param {string} locale The locale used for this sentence part.

@constructor
function( sentencePartText, auxiliaries, locale ) {
	this._sentencePartText = sentencePartText;
	this._auxiliaries = auxiliaries;
	this._locale = locale;
	this._isPassive = false;
}