In the following passage, some of the words have been left out. Read the passage carefully and select the correct answer for the given blank out of the four alternatives.
It is necessary, then, to keep our ____________ acts under some surveillance of attention, to pass them in review for inspection every now and _________, that we may discover possible modifications which will make them more serviceable. We need to be __________, constantly to find out better ways of doing things. Habit takes care of our standing, walking, sitting; but how many of us could _________ improve his poise and carriage if he would? Our speech has become largely automatic, but no doubt all of us might remove _____________ of enunciation, pronunciation or stress from our speaking.