My sister has not come back yet. -
I have been writing emails for three hours. -
Luke has written four books. -
We haven't been to Sweden yet. -
I have lost my phone and I can't call you. -
Mary and Jane have been travelling since July. -
I haven't been swimming since May. -
I have just left my job. -
Who have you been talking to for an hour? -
Erica has not been listening to you all this time. -
They have been studying philosophy for five years. -
Have you ever met Helen? -
Jack has been decorating the house all summer. -
There has been an accident. -
Has Max been exercising lately? He looks great! -
Where have I left my bag? -
Charles has been teaching at the university since August. -
I haven't seen Lisa today. -
They have never met Alex. -
Have you been reading this paper for two hours? -