adverb:at the present time or moment
Now I know how to read this sentence.
noun:the present time or moment
Now is the best time to start your project.
adverb:used to introduce a point, a command, or a question, especially to emphasize the speaker's impatience or insistence
Now, listen to me carefully.
conjunction:since or because of the fact that
Now that you've finished your dinner, you can have dessert.
