改错（每小题有一处错，请将它划出，并改正在后面的横线上。）
1、Does your mother busy with her housework now?                       ____ 
2、Don’t worry. Let Meimei helps you.                                    ____ 
3、My brother likes fish very much, but my favourite is tomato.                ____ 
4、How do you speak it in English?                                       ____ 
5 、I get up late on every Sunday morning.                                  ____ 

如图，D是△ABC的边BC上任意一点，E、F分别是线段AD、CE的中点，且△ABC的面积为24cm²，求△BEF的面积．