Many experts hold the view _____ teacher development is ____ the key to better education lies.
In 1960, this was the longest bridge that __________.
―Why? Where is the key to the sound lab? ―Dear me! You _______ it in the taxi!
―What were you doing when I called you yesterday afternoon? ―I ________ my homework and I was starting to take a bath.
―What’s the matter? You look worried and restless. ―Oh, nothing really serious. As a matter of fact, I ______ of my graduation thesis. I have to hand it in soon.
One of them told me, “This is the first time I ________ to the capital to attend the flag-raising ceremony.”