l think (happy)is the most important

l think (happy)is the most important
lt is (luck)that he has won the first prize in the competition
To go to the beach snd have a swim is nice(保持原意)
— —nice to go to the beach snd have a swim.
Think it over and you won't make such a mistake(保持原意)
___you think it over,you_____not make such a mistake