One area of academic writing that causes serious difficulties is the use and syntax of adverbials. In English, adverbials most commonly take the form of adverbs, adverb phrases, temporal noun phrases or prepositional phrases. Many types of adverbials (for instance reason and condition) are often expressed by clauses (source: Wikipedia).

An adverbial is a construction that modifies a verb in some way, thereby changing the verb’s meaning. Some examples include:

  1. Our research results varied significantly (verbal – how)
  2. The study took place in the classroom. (prepositional – where)
  3. The data was analyzed immediately. (temporal – when)
  4. Further research is necessary since the findings were inconclusive. (clausal – why)

In every sentence pattern, the adverbial is a clause element that tells where, when, why, or how. There can be more than one adverbial in a sentence. In addition, the same adverbial can be moved to different positions in a sentence, making their use particularly tricky. Keep in mind that the basic English sentence structure is Subject + Verb-Object. Adverbials can be placed before or/and after this cluster, as in:

Surprisingly, the research showed no conclusive evidence despite our initial efforts.
(adverbial)    (subject)  (verb-object                            ) (adverbial).

Please note that an adverbial is NOT placed between the verb and the object:

*We decided at once to conduct the research.
We decided to conduct the research at once.

In fact, it is best to think of the verb and its object as a single, inseparable element (verb-object).