This study classifies the word order relationship between complement and object by type resulting from various causes and analyzes its characteristics. The syntactic constraints on the location of the object are summarized and described, and the word order relationships based on it are categorized into three main types. By dividing the word order relationship between the verb-complement structure and the object into the post-object pattern, the pre-object pattern and the intermediate-object pattern, the characteristics are all deeply related to the ‘principle of word-order iconicity’. It is in line with the fact that learners unconsciously consider the relationship between the verb and object the closest, making it difficult to separate them. In order to reduce word order errors resulting from it, it is expected that there is a need to emphasize the separation of verb-object structure in the teaching and learning process of complements and to reexamine the location of verb-copying sentences that appear commonly in the word order of the complement and object.