It was raining heavily. Famers went on working on their farms

--> Although It was raining heavily, Famers went on working on their farms

Nam usually helps me with Math

--> I am usually helped by man with math

My father doesn't smoke any more

-->My father used to smoke

Never pick food out of your teeth with your finger nails

--> You shouldn't pick food out of your teeth with your finger nails

Mai'd rather traditional dance than moderns ones

--> Mai prefers traditional dance to moderns ones