except, unless: These words are not synonymous. Avoid such locutions as "You will not enjoy it except you earn it." Say rather, "You will not enjoy it unless you earn it."
exceptionable is to be distinguished from exceptional. Exceptionable conduct is that which is out of the common and forms the exception to the rule.
"Taxes on commodities are either on production within the country, or on importation into it, or on conveyance or sale within it, and are classed respectively as excise, customs, or tolls and transit duties." (bk. v. ch. 3, p. 562.)
Thus, excise is a charge on commodities of domestic production; customs is a charge or duty assessed by law levied on goods imported or exported; tolls are charges for special privileges as, passing over a bridge or a turnpike.
excite, incite: Exercise care in the use of these words. Excite means to produce agitation or great stir of feeling in; incite is to rouse to a particular action.
exemplary should not be used for "excellent." That which is exemplary serves as a model or an example worthy of imitation: that which is excellent possesses distinctive merit or excels that which is good or praiseworthy.