综合填空
   Jim is a schoolboy. He is 13 years old .He's in Class 3,Grade 1. He always____ (get ) up early and he often____(go) to school by bike . He ____ (like) English,Chinese maths and some other lessons. He enjoys singing and____ (dance) .But now he ____ (have) an English class . Look. Some of the students____  (read) books and some of the students____ (write) the new works. They are working hard .But tomorrow is Saturday. They won't have any lessons .He and his classmates ____ (play) football tomorrow moring. They ____ (check) emails tomorrw afternoon.  They  ____ (watch) TV tomorrow evening .I think they’ll have a good time .

已知抛物C:y²=8x 与点M（-2，2），过C的焦点，且斜率为K的直线与C交与A,B两点，若$\overrightarrow{MA}·\overrightarrow{MB}=0$ ，则 k= （  ）