TASK DEFINITION: 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.
PROBLEM: Theobroma oil can exist in four different polymorphic forms of which only ____ is stable.

SOLUTION: one

PROBLEM: Brook stickleback have prominent mouths, large eyes and ____ to six spines on their backs.

SOLUTION: four

PROBLEM: Rotifers fall into ____ salinity categories - marine and freshwater.

SOLUTION:
two