He was sleeping ____ someone knocked on the door.

_____ the police thought he was the most likely one, they could not arrest him since they had no exact proof about it

ss has been very good so far.We are,_____,confident that the work will be completed as expected.

who have regularphysical exercise seldom catch a disease like H1N1 Flu, ______

The researchon the new flu virus vaccine is challenging and demanding. Who do you think cando the job —______ mystudents have a try