Syntax means "arrangement" of words into sentences and sentences into paragraphs.
Chinua Achebe's syntax in Things Fall Apart is his word choice and sentence complexity and variety. His style is not macho, like Hemingway's, but it is definitely manly. Written in English, the novel makes use of several Ibo words and phrases (defined in a glossary in the back) such as: "agbala" (woman); "chi" (personal god); and "obi" (large round hut). These words give the novel authenticity and blend the two languages and cultures.
Achebe's English words are otherwise high-frequency words (words we use in every day speech). He uses a mix of simple and compound sentences to tell the story in a plain style (without much adornment). Descended from the oral tradition, much of the narration is meant to be heard, as if we are sitting around the tribal circle listening to Okonkwo or Obierika. According to Enotes:
Achebe develops Things Fall Apart through a third-person narrative—using" "he" and "she" for exposition—rather than having the characters tell it themselves. Often speaking in the past tense, he also narrates the story with little use of character dialogue. The resulting story reads like an oral tale that has been passed down through generations of storytellers.
Achebe also makes much use of proverbs to pass along this oral tradition. In addition, he uses many songs, chants, sounds (onomotapeia), and ceremonial customs involving food. All of these passages reveal a syntax that not only moves the story along but passes on tradition from the Ibo-speaking African tribal to the English-speaking post-colonial West.