Before revision: In the 1940s, the invention of semiconductor devices made it possible to produce solid-state devices, which are smaller, more efficient, reliable, durable, safer, cooler, and more economical than thermionic tubes.
After revision: In the 1940s, the invention of semiconductor devices made it possible to produce solid-state devices, which are smaller, more efficient, reliable, durable, andsafer, cooler, and economical than thermionic tubes.