The Great Wall is ____________ wall in the world. There are many stories about it.

All the government leaders and policemen in Thailand must see to ______ that every citizen should stay safe and sound in the terrible flood.

The eraser is not mine．It’s__________．

It is very kind _____ you to help me carry the heavy box.[ ]

The English exam is not difficult, is it?–________. Even Tom ________ to the top students failed in it.