________ into use in April 2012, the hotline was meant for residents reporting water and heating supply breakdowns.
We have the list of items we want, which means that we know ______ what we want.
It is said that sandstorms will become more________ as a result of global warming.
The Sunday of May is Mother’s Day and a time to be _____________ to our mothers.
We have been trying hard to find out the ____________of the homeless man, but without luck, no one can tell who he is.
You can get to Hong Kong using different kinds of ________, by air, by sea or by land.