Pls i want a quiz or test about tenses

However, the idea of real-life people living in what would become the united states for thousands of years before columbus ever left spain never dawned on me. what would be the best way to revise this sentence for greater clarity? a) however, the fact that columbus left spain thousands of years after people settled what would become the united states never dawned on me. b) it never dawned on me, however, the idea of real-life people living in what would become the united states for thousands of years before columbus ever left spain. c) however, the fact that people were already living in what would become the united states for thousands of years before columbus ever left spain never dawned on me. d) however, the idea never dawned on me that long before columbus ever left spain, real-life people lived for thousands of years in what would become the united states.

If a sentence is a run-on, correct it. if it is correct as written, write correct. 1.)i looked down. i saw that the well was apparently dry. 2.)we read the preamble to the constitution, our group felt anew the power of those words. 3.)the boy had trouble with the decimal point when multiplying he always put it in the wrong place. 4.)the thermometer broke, the mercury spilled onto the floor. 5.)i mislead my car keys, my house keys were also gone. 6.)it is against the law litter, neveretheless, people do it. 7.)ann threw away the check, but she eventually recovered it. 8.)i generally like the climate of the area where i live i do not enjoy subfrezzing winter temperatures. 9.)everyone should be polite, however many people are rude. 10.)i made my own chili to eat it one needs an iron stomach.

What syllables in "arrived" are stressed/unstressed?