Charles Goodyear ______________ (make) the first sneakers in 1917.
Charles Goodyear made the first sneakers in 1917.
Velcro ______________ (invent) by George de Mestral. It ______________ (use) to fasten two materials together. Many companies ____________ (use) Velcro on their clothing products.
Velcro was invented by George de Mestral. It was used to fasten two materials together. Many companies use Velcro on their clothing products.
Roy Plunkett ____________ (invent) Teflon in 1946. Teflon ______________ (apply) to cookware eight years later. Many cooks now ____________ (use) non-stick and pans.
Roy Plunkett invented Teflon in 1946. Teflon was applied to cookware eight years later. Many cooks now use non-stick and pans.
The microwave oven ______________ (invent) by Perry Spencer in 1947. The first microwave ovens ____________ (weigh) 750 pounds and ____________ (cost) $5,000.
The microwave oven was invented by Perry Spencer in 1947. The first microwave ovens weighed 750 pounds and cost $5,000.
Randolph Smith and Kenneth House ____________ (develop) the first battery-operated smoke detectors for homes. Today, smoke detectors ______________ (require) in homes, schools, and apartment buildings.
Randolph Smith and Kenneth House developed the first battery-operated smoke detectors for homes. Today, smoke detectors are required in homes, schools, and apar
VCRs ______________ (introduce) in 1971. They ____________ (allow) families to rent movies at video stores. In 1995, many companies ____________ (work) together to develop DVD technology. Today, more DVD machines ______________ (sell) than
VCRs were introduced in 1971. They allowed families to rent movies at video stores. In 1995, many companies worked together to develop DVD technology. Today, mo
The pop-top can ______________ (develop) by Ermal Fraze. The top and the ring ____________ (stay) attached and ______________ (negative cause) litter. Before 1973, soda ____________ (bottle) in glass bottles. Then, Nathaniel Wyeth _________
The pop-top can was developed by Ermal Fraze. The top and the ring stayed attached and negatively caused litter. Before 1973, soda was bottled in glass bottles.
