Oil prices have risen by 32 percent since the start of the year, ____ a record US$57,65 a barrel on April 4. [ ]

While in university, we were offered a number of afterschool activities to _____ our social skills．

To get a better grade, you should __________the notes again before the test.

Children will work actively if _______. 

I always feel nervous when I answer the questions in class. —_________. Just smile and try your best. Everything will be OK.