Congo is the only major river which crosses the equator twice. It is the second largest river in Africa after Nile and the second largest river in the world.

A. Agraphia is an acquired neurological disorder that causes a lack of ability to communicate through writing, either due to motor dysfunction or the inability to spell.

B. Central agraphia usually involves language areas of the brain, causing difficulty spelling or spontaneous communication, and often co-occurs with other language disorders. Some types of central agraphia include:

1. Alphabetical agraphia – In this, there is difficulty in recognizing or writing letters.

2. Semantic agraphia – It involves difficulty in understanding or writing words.

3. Orthographic agraphia – It involves difficulty in applying spelling rules.