This paper is an attempt to explore that in certain situations ,the adjectives functioning as subject complement can not semantically be satisfied unless syntactic complementation can be added ,this is called as subject complementation .This can be realized by; prepositional phrase, wh clause ,that clause ,to infinitive clause as stated by Quirk et al (1985:1220)In this paper other structures namely , ing non finite clauses can be added .It is concluded that syntactically some structures can not satisfy their meanings ,unless it is fulfilled by complementations , ,although it is optionally added .The test in this paper is conducted on [20]students ,from fourth year ,English Department .The test consists of [10]sentences with different structures .The results show that the students are weak to some extent to recognize the subject complement.