This book makes a didactic and grammatical examination of the use of defined determiners among Congolese middle school students in 6th grade. He appreciates their skills in using definite determiners with nouns. It was first necessary to categorize these errors according to whether they are Gender Agreement Faults, Number Agreement Faults, Double Determination, Phonic Confusion, Bad Plural. Then, research the causes of this reality and finally, propose solutions likely to reduce these errors on the copies.