David had prepared carefully for the chemistry exam, as he wanted to be sure of passing it at the first _____.
Tom is the only one of the students in our school who_____late this morning.
You can find whatever you need at the shopping centre,_____is always busy at the weekend.
These newly-produced cars are sold at so low a price_____people expected.
The most important thing_____we should pay attention to is the first thing _____I have said.
The World Wide Fund for Nature is an organization_____aim is to protect wildlife.