Weregretto________thatitmaynotbepossibletodealwitheveryrequest.

Theenginehasbrokenandtheboatis______onthewater.

_______themovieIwouldhavefinishedmypaperlastSunday.

We were told that Sue would be ideal for the job, but she ________ badly when we talked to her.

Humanbehaviorismostlyaproductoflearning________thebehaviorofanimalsdependsmainlyoninstinct.