What I like about Harvard is ________ there's the old classical look—there are parks and traditional buildings.

We should do what we have to do ______ we can do what we want to do in the future.

Just wait here, ______ you can hang around for a while. Your turn is half an hour away. 

Telephone users sometimes complain about unreliable service and       they consider unfair charges.

 ______ you make a promise, you should keep ______.