It is generally believed that teaching is ________it is a science.
Is this the reason____ at the meeting for his carelessness in his work?
You stepped into the lab with your shoes on? You’re _______ to take them off before you enter it.
—We could invite John and Barbara to the Friday night party. —Yes, ______ ? I’ll give them a call right now.
Jack wasn’t saying anything, but the teacher smiled at him _______he had done something very clever.
A bank is the place ______ they lend you an umbrella in fair weather and ask for it back when it begins to rain.