Experts have found that the disease will lead to a greater increase in the number of sufferers unless ________ seriously when the symptom first appears.

The decision has been made________a new school building be built next month.[ ]

Can we get everything ready by the weekend? —It all depends on______we can get Mr. Green’s cooperation（合作）.

What he said was not relevant _________ the matter in hand

________ you ought to do now is to see a doctor atonce