请说出优化车底使用的方法

tShe doesn’t know _________________ mde her dughter so sd this morning.wht ws it B．why it ws tht C．how tht ws D．wht it ws thtA．what was itB．why it was thatC．how that wasD．what it was that

the student’s sttements, why hs she not strted thessignment Becuse she hs prt-time work to do. B．Becuse it ws relly bigssignment. C．Becuse she hsn’t spent time in the librry. D．Becuse she ws doing work fornother course.A．Because she has part-time work to do．B．Because it was really a big assignment．C．Because she hasn’t spent time in the library．D．Because she was doing work for another coursE．