Decide whether the following sentences are the periodic sentences or not. If it is, fill in Y. If not, N. She decided to study English though she was interested in music. _______ Scientists in the twentieth century have made many great discoveries. _______ Without good study habits, you cannot make great progress in English. _______ He was sitting before a fire in a large armchair when we entered. _______ Having passed the house every day for two years,and knowing that the man was a cripple, I could not believe what the next-door neighbor told me. _______ In addition to his salary, the salesman received a bonus for his excellent work. _______ Mr. Smith, who is a high school teacher, asked me to help him. _______ It is a truth acknowledged that a single man in possession of a good fortune must be in want of a woman. _______ She insists on finishing the assignment in spite of her headache. _______ He is found guilty because he could not provide. _______