The local government has been accused of not responding _________ to the needs of the homeless in the flood-stricken area．

A model or an experiment in a science class can help us see things which would       remain hidden．

If they don’t change the way they’re working on the issue, the result will       turn out to be just the opposite of their wish.

Don’t defend him any more. It’s obvious that he ______ destroyed the fence of the garden even without apology.

The conservation area is very important for preserving many animals and plants, which would ______ run the risk of becoming extinct.

Several musicians say they consider it the greatest musical composition _______ written.

As is known to all language learners, the newly learnt words will soon be forgotten unless ______ used in everyday communication.

The boys are doing no harm; they are ___ playing．