However, at times this balance in nature is disturbed, ____ a number of possibly unforeseen effects.
— Did Peter fix the computer himself? — He ________, because he doesn't know much about computers.
Without my glasses, I couldn’t _______ whether that figure on the blackboard was a three or an eight.
Dogs have a very good ___________ of smell and are often used to search for survivors in an earthquake.
— Someone might see us. — ___________? We are not doing anything illegal.
— What do you expect your son to succeed in? — _________ the entrance exam.