—Ready to give up guessing, Sandy? —No, no. Hold on! I think I _______ at the answer now.
Asimov began having his stories ______ in science magazines in 1939.
It was ______ Asimov was eleven years old ______ his talent for writing became obvious.
—Sorry, I made a mistake again. —______. Practice more and you’ll succeed.
I’d like to ______ you _______ your success on the experiment.
It is generally believed that teaching is ______ it is a science.