Not only ____ strict with us, but also ____ for us.
The reason _________ the little actress has been such a success is ________ she is both clever and hardworking.
I have no idea _______ we can do with these waste materials.
FBI stands _________ Federal Bureau of Investigation.
His work _________ have been completed; otherwise, he wouldn't be enjoying himself on the beach.
He wondered __________ the pyramids were built.