—Smoking is bad for your health.—Yes, I know. But I simply can't________.
-When shall we set off? -We ____ start off at five o’clock if it ___ raining by then.
She won’t lose weight ___ she keeps a diet and takes exercise every day.
-Who is the lady standing over there? -I am not sure, but it may be ___ from the provincial government.
It was not until he saw his mom _________.
John is very lazy. He falls ______ behind among the students.