Answer:
What occurs four times in every week, twice in every month, only once in a year but never in a day?
What is seen in the middle of march and april?
Something you carry while singing.
What is the center of gravity?
I am the yellow hem of the sea's blue skirt.
It flows out of the soil, It burns you if it boils, And holds us in its coils, More valuable than gold, As black as it is old.