Most whales must come up for air after several minutes, _______ a few can stay under water for an hour or more.
As we all know, the child is his __________ son and is not genetically __________ to him, but he always sees him as his own.
They no longer have to __________ large numbers of temporary workers to do the harvesting.
Eating a __________ diet helps us to keep a __________ of cool and hot.
They improved the software to __________ for people to use computers.
The English teacher laid particular __________ on the need of reading aloud.