—If we take a plane，we’ll of course have arrived in London by the next weekend.—Don’t be too sure.We should ________ the weather factor.What shall we do if it is foggy?

The new president spoke at the APEC meeting for nearly an hour without ________ his notes.

Your________as a student will be excellent if you develop a habit of reflecting on how you learn.                                                                (2012·浙江，7)

More and more attention has been drawn to the fact that many children are ________ in the countryside when their parents flood into the cities for jobs.

 You’d better take a map with you when you go to a strange place ___ you get lost.