In ISSB, this test is taken by Psychologist to find out your personality traits and character. Sentence complete by a candidate is related to the candidate life.

Purpose of Sentence Completion Test:-

Sentence Completion Test is used to analyze candidate thought, motives and attitudes and conflicts. A psychologist usually judges candidate personality by reading the sentences completed by a candidate.

The procedure of Sentence Completion Test (SCT):-

The candidate is provided with a paper on which 26 partial incomplete sentences are written. You have to complete the sentences in 6 minutes. There are two pages given two you one by one. Both of which have 26 sentences on each to complete. So, the total sentences are 54.
The same situation is for English Sentences.

Tips for a candidate:-

It is not necessary for a candidate to complete all the sentences but it is good to complete all sentences. Because it will show your resourcefulness.
Be natural and true in completing the sentences. Because the sentence you complete is based on your own life(It is considered by Psychologist).