Many ....... and ....... ....... on the river.

Alliteration is when two or more words start with the same letter or sound. An example would be 'crawling caterpillars'. Tongue twisters are often good examples of this way of writing - try saying 'Fred's friends fried Fritos for Friday's food'! The technique can be used in writing and speech to interest your audience, or to bring some humor to your sentences.