Given a sentence, fill out the missing word with a 'no' or a number (between zero and ten). You should write the numbers with english alphabet, like: four instead of 4.

Q: Snow is on the ground for close to ____ months out of the year.

A: seven
****
Q: Biological islands are of ____ general types, geographical and ecological.

A: two
****
Q: Blood flows in one direction through the four chambers with the aid of the ____ heart valves.

A:
four
****