'Exert' means to apply force on influence over something else, this can be in a negative or positive way. In this quotation, it means that language, if used correctly, has the ability to express a 'hidden power'. It's also worth mentioning that the simile is relevant as the moon has an influence on the level of tides on Earth.
Well you got to give us the name of the book or else we are clueless on what do help you on
<span>The given choices are all
relevant to what is asked. They can all be used depending on the type of essay
you are crafting. If you are writing a humorous message, a humorous anecdote as
an ending can be effective. If you’re writing a formal, informative essay, a formal summary of your overall message
would make sense. If you are promoting your own ideals and beliefs, you can
either ask the reader to take some kind of action or end on a note that's likely to stick
in the reader's mind. There is no definite answer here since it would
largely depend on your essay type. </span>
