Modern science has given ____clear evidence ____ smoking can lead to many diseases ____ it’s time for us to take measures.

It was my sister ________ first had the idea to cycle along the entire Mekong River.

 It is almost five years_______ we saw each other last time.   

___________, education is about learning and the more you learn, the more equipped for life you are.

_________ wonderful news report he wrote! All of us were proud of him.