New traffic rules that took effect on January l, 2013 are much stricter______ than          in the past．

It’s a little surprising that a house made of wood or bamboo may stay up in an earthquake while _______ made of steel and concrete may fall down.

I’m moving to the countryside because the air there is much fresher than ________ in the city.

 Whom can you trust, if not _______ ?

Meeting my uncle after all these year was an unforgettable moment ,_______I will always remember.