________ surprises us most is that she doesn't even know _________ the difference between "speak" and "talk" lies.
—It’s the first time for me to stand on the stage. —______. I believe you can perform well.
--I’ m going to swim with my father in the river this weekend. --_________.
_______ finish their task ahead of time, the students worked harder and harder.
They became good friends during the war, and since then their lifelong friendship has _______ tests of life and death.
It was on March 11,2011 ________ a strong earthquake hit Sendai, Japan.