Sure, here are the completed sentences:
I have been writing emails since 10:00 this morning. So far, I have finished five.
Jane has eaten lunch already, so she is not hungry.
It has been raining all week. The roads are still wet.
Laura is at the mall. She has been shopping all morning.
Jack hates butter. He has never eaten it.
They have been traveling through Europe for ten days.
So far, it has cost over $200 million dollars.
The boys have been playing soccer all afternoon. They have caught a train home.
Ben has loved his pet all summer.
Kelly is standing on the corner. She has been waiting for you.
I have parked a car in the street across from my house.
Alice has lived in the same house since 1990.
Dan has been helping me a lot with my homework.