It's 12 o'clock now.The following people have been busy all morning .Look at the information and say what they have been doing and how long they have been
doing and how long they have been doing it for,as in the example.
пример lynn's been tidying the garden for three hours/since 9 o'clock.

Kim has been cleaning windows since 11 o'clockMaria has been revising for exams since 10:30 amJim has been programming computer since 11:30 amDavid has been washing car since 10 o'clock