Here is so heavy a stone that no man can __________ it up.
Today a large coal-fired power plant can give out in a single year as much poisonous gas as was blown out by the May 18,1980 outbreak of Mount St. Helens, ______ some. 400,000 ton.
So difficult ________ it to live in an English-speaking country that I determine to learn English well.
The medicine is supposed to cure this disease, but I’m not sure it .
----No one is so ____ about his joy as Doctor Li. ----You are right. He devotes all his time and energies to his cause.
Hundreds of _____ of science fiction are published each year in our country.