So you're given a sentence where if there is a particular word in the sentence then the output is 1, if it is not there then the output is 0. For example:

Sentence = 'The birds in the field are eating bird seed';
Not_allowed = 'field'

so the output will be, because field is found in the sentence:

Output = 1; 

Another example:

Sentence = 'If the sky is blue on earth, what is the sky color on mars?';
Not_allowed = 'oven'

so the output will be, because oven is not found in the sentence:

Output = 0; 

That is it!

Have Fun!