These function as adverbs and, as such, many of them can be replaced by simple adverbs. Some examples appear below:
From the foregoing, it is evident that many adverb idioms begin with prepositions and end with nouns. But there are a few others that may begin with adverbs and end with adverbs, or with determiners and end with nouns, or with adverbs and end with nouns, or with conjunctions and end with nouns, or even with nouns and end with nouns. Their form notwithstanding, adverb idioms tend to perform adverb functions.
Some adverb idioms are, however, not replaceable by simple adverbs but by corresponding adverb phrases. They are more or less adverbial phrases with unique meanings. See the following examples:
- by hook or by crook (by any means – fair or foul).
- armed to the teeth (completely and elaborately armed).
- lie in one’s teeth/throat (lie shamelessly).
- up and down (backward and forward).
- in broad daylight ( in day-time).
- at the eleventh hour (almost too late).
- at the first blush (at first sight).
- as it were (so to speak).