Syntax is the study of sentence structure in a language. It inspects how words are combined into phrases and sentences. Every language has its own syntax or rules of word order in a sentence. The subject-action-object order is an example of the structure in English.
The following arrangements are a few basic sentence structures in ASL.
TOPIC + COMMENT where topic is the topicalization and comment can be a statement, question, or predicate. It is also known as SUBJECT + PREDICATE.
Also, TIME + SUBJECT + PREDICATE or TIME + TOPIC + COMMENT.
SUBJECT + ACTION + OBJECT
Topicalization is a process of establishing a topic in a sentence of the paragraph or a paragraph of the paragraphs or text in ASL. It is like a sentence opener. A visual-manual speaker begins with a topic to open what s/he talks about and then proceeds to make a statement or question.
There are two common syntactical order of sentence: SUBJECT-ACTION-OBJECT and SUBJECT-OBJECT-ACTION. These arragenments depend on the spatial, temporal, and kinetic structures of a subject, object and direction.
Time also can be added to the arrangement: TIME + SUBJECT + ACTION + OBJECT.
You may also be interested in topicalization: topic-comment structure.