b) That which happens every four years. -quadannual

c) That which happens every half year. – semiannual

d) That which occurs time after time. -repeatedly

e) That which happens once in three years. -Triannual

f) That which happens after 100 years. – centennial

exactly the same question wioth exactly the same answers but now you can give me best answer twice lol:)

2. Leap Year (well it DOES happen every 4 years, LOL)

3. Biannual

4. continual

5. Triennial

6. centennial

(I think?)

Quad annually

every 2nd quarter

tri annually

every century

b)quad-anually

c)semi-anually

d)re-occuringly

e)tri-anually

f)centennial

quad? annual

perpetual

tri annual?

centinnial