So difficult ______ it to work out the problem that I decided to ask Tom for advice.
It’s recommended that the government ________ the local people to reduce the carbon emission in their daily lives.
No matter how hard the government has tried to search for it, the missing Malaysian flight MH370 is still nowhere _________.
Animals are different from plants ________ they can move when they are attacked by others.
The approach _________ the problem is contrary ________ our expectations.
She is always thinking more of herself, seldom, ________, offering to help others.