because they worked really hard on whatever they were doing.
The Phoenicians improved upon the Sumerian invention by when the Sumerians invented the first writing system (symbols and cuneiform) the Phoenicians invented the alphabet which was easier.
The Greek invention that aided navel travel and that was improved upon by the Muslims was Greek fire.
It has already been improved. Pencils have many colors and hardness values. Pens are a type of pencil with ink instead of graphite.
There was no single "original invention".
the sumerians strove to please their gods because they belived their god could bring them good or bad things upon them
Both "improve" and "improve upon" can be used, but they have slightly different connotations. "Improve" typically means to make something better in a general sense, while "improve upon" suggests building on an existing idea or standard to make it better. Use "improve" for straightforward enhancements and "improve upon" when referring to enhancements that build on prior work or concepts.
Johannes Gutenberg Gensfleisch
Several chance encounters influenced Thomas Edison's spirit of invention. In 1862, he rescued a child from the train tracks As a reward, the child's father taught him telegraphy. Telegraphy skills set him on the path to some his greatest inventions afforded him the opportunity to travel, perfect his scientific experiments and start the Invention Factory. Alexander Graham Bell's invention of the telephone inspired him to experiment and improve upon the model. His meeting with Edward Muybridge led to the invention of the motion picture.
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One way the Phoenicians influenced later people was through their navigational techniques. They were amazing inventors and created several devices still relied upon today by navigators. They also invented the alphabet which became the basis for the Greek and Roman alphabets, which were the basis of today's writing.
IM PRETTY SURE IT WAS THOMAS ALVA EDDISON WHO HELPED ALEXANDER GRAHAM BELL IMPROVE HIS TELEPHONE INVENTION. LISTEN I AM ALONE AND AT CROSSROADS
to improve upon the older telephones