15. --- Who are the teenagers gathering at the school gate? --- Well, if you _____ know, they are all my visiting students.
---Could you help me take care of my pet dog on the 19th? --- I’m afraid I’m not that day.
---My Dad began to teach me English when I was eight. ---Wow. You must have studied English for six years, ?
--With the country’s pension fund gap becoming wider than ever, retirement age should be postponed immediately. ---Easier said than done. we take all factors into account, we shall be faced with some other social problems.
-- We hadreally smoggy December this year. --- I can’t rememberwinter when air was polluted so severely.
At present, there are many instances the governments distribute money to the citizens worldwide, but the sources of fund are still limited.