The subject-predicate compound is composed of two elements, whose relation is one in which the first element is the subject of the second element. Here are some examples of subject-predicate compounds:
It can be modified by an intensifier, such as hen very
It can be negated. For example,
It can be the A element in an A-not-A question:
Li, C. N., & Thompson, S. A. (1989). Mandarin Chinese: A functional reference grammar (Vol. 3). Univ of California Press.