1, there is only 1 MAIN star.
There are hundreds of stars in the constellation Pegasus.The main stars are:MarkabScheatAlgenibEnifHomamMatarBahamSadalbariFor details about all the other stars, see related link.
It has 9 main stars, but many more.(:
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There are about 43 stars in the Delphinus constellation. The brightest star in Delphinus is called Sualocin.
the constellation Draco has 17 stars some people say it is 14.
There are 15 main stars but many more. See link
Constellations are defined by MANY stars not just one. Given this fact your question is obviously meaningless.
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There are 8 main stars with an additional 9 stars in the asterism. There are over 80 stars in the Gemini constellation [See related link]
There are 12 stars that make up the constellations main outline, but there are many other stars "sprinkled" in among it.
18 is the stars of the constellation hydra
some people think 21 main stars and others 7 main stars.