Explanation:

- Article 343 (1): ?? This article states that Hindi in the Devanagari script shall be the official language of the Union. It establishes Hindi as the main language for official purposes, with English as an associate language for a period that Parliament may decide.

- Article 343 (2): This article talks about the continuation of the use of English for official purposes for 15 years from the commencement of the Constitution.

- Article 344 (1): This article provides for the formation of a Commission and a Committee to make recommendations for the progressive use of Hindi for official purposes.

- Article 343 (3): This article allows Parliament to legislate on the continued use of English beyond the initial 15-year period.