President Obama told television viewers that he saw ______ as his duty to run for a second term.

---We have red and yellow T-shirts. Which color do you like?---I’m afraid _______. I think blue will be OK.   

Mr. Smith doesn’t like all that empty talk between Susan and Joan, which he thinks will definitely get them ________.

-Which of the ways should I take to the village? - way as you please．All seem to be equal in distance．

. _________ is good for you going to bed early and getting up early.