The chairman thought _______ necessary to invite Professor Smith to speak at the meeting .
| A.that | B.it | C.this | D.him | 
All foreign visitors are requested to _____ with the regulations in this area.
| A.agree | B.comply | C.consent | D.conform | 
These continual _____ in temperature make it impossible to decide what to wear.
| A.alterations | B.vibrations | C.waves | D.fluctuations | 
The illness from which Mary is suffering has now been _____ as hepatitis (肝炎).
| A.diagnosed | B.determined | C.deduced | D.discovered | 
A completely new situation is likely to _____ when the school leaving age is raised to 16.
| A.arouse | B.rise | C.arise | D.abide | 
I must go now. _____, if you want that book I'll bring it next time.
| A.Incidentally | B.Accidentally | 
| C.Occasionally | D.Subsequently |