Переведи They boysare tired. They have been playing basketball for an hour and a half. Alex has been talking on the phone since 5 o'clock. The telephone has been ringing all day. Mr Williams has been writing his book for half a year and he hasn't finished it yet. People have been working on this problem since the beginning of the century. John has been washing his car since nine o'clock this morning. Sarah has been writing her project all day. We have been learning the poem for an hour a half.