前缀 afore- = Before or previously
Words beginning with afore- are now archaic or formal and in some cases have been replaced by words or phrases employing before. Examples are aforehand, beforehand and aforetime, in former or past times. Aforementioned and aforesaid refer to a thing or person previously mentioned; aforethought, premeditation, now usually appears only in the formal legal term malice aforethought, the intention to kill or harm that distinguishes murder from accidental killing. Afore, as a free-standing word meaning ‘before’, is now only in dialect use.
a-2
Towards, of, in, into or at; marking some ongoing process or state; movement onwards or away.
[Old English prepositions of or on (sometimes as unstressed an), or the Old English prefix a-.]
The Old English prepositions were originally separate words, but became reduced to a- and attached to the words they once modified. The process can be seen in alive, which in Old English was two words, on līfe, literally ‘in life’; others of similar type are aside, akin, and anew. Some examples are verbs derived from Old English a-, which had an idea about it of an action or an intensification of an action: arise, abide, and awake.
Some adjectives imply a continuing or active state, and have much the same force as a present participle ending in -ing (see -ing2): ablaze, abuzz, afire, afoot, aglow, astride. Others combine the prefix with a present participle, usually hyphenated; such words imply an ongoing process or activity: a-brewing, a-roving, a-hunting, a-wasting; though they are mostly now archaic, literary, or dialectal, the form has had a small revival in recent decades, as in Bob Dylan's song lyric The times they are a-changing.
-ing2
Forming the present participle of verbs, and adjectives from nouns.
[Middle English: variation of earlier -ende, later -inde, subsequently completely identified with -ing1.]
The present participle is the form of the verb used to make a continuous tense, as in he is climbing, they are walking, stop what you are doing. Any verb can form its present participle by adding -ing in this way. Such participles are often used as adjectives: he is a charming man, she is his golfing partner. Some adjectives of this type are formed from nouns instead: cunning, hulking, swashbuckling.
-ing1
Forming nouns derived from verbs.
[Old English -ung, -ing, of Germanic origin.]
Such nouns express the action of a verb (fighting, muttering, shaving, thinking, working), often relating to some occupation or skill (banking, fencing, glassblowing, modelling, silversmithing, welding); sometimes they indicate a single instance of the action (a ruling, a scolding, a wedding). They may also denote a material used for a process, or associated with it (bedding, cladding, clothing, flooring, piping, wadding); a few of these are formed from other nouns without a corresponding verb (sacking, scaffolding). For nouns such as sibling or weakling, see -ling.