Overhaul

Directions: Some words in the passage below have been highlighted. Select the best meaning for the corresponding word.

The first plunge into public speaking often reveals quite unexpectedly the physical strain imposed on the nervous system. Muscles controlling your lungs, your body, or your memory may need strengthening. Mannerisms which divert physical energy may need checking, deep breathing may have to be practiced. But once you are aware of these necessary adjuncts to public speaking, you can overhaul the machinery and be reasonably confident of withstanding the strain. The human machine, like all machinery, breaks down occasionally and bad health or brain tiredness will react on your speaking ability, but just as no healthy minded person should live in constant fear of illness, so no trained speaker should anticipate physical breakdowns. Should mental blackouts occur, it is not necessarily a tragedy, and auto-suggestion can be practiced, or methods of diverting audiences can be learnt, or appeal by frank confession of your mental lapse can be tried. Any of these remedies can help overcome fear and restore self-confidence.