Success _________three key factors: diligence, talent and luck, of which the first one is of great importance .
—I don't know what I should have done without your help. — __________.
A major issue was put forward by some representatives at the conference __________ the teachers in the remote areas were underpaid.
I have little doubt __________ the plan will succeed.
__________ many benefits, cell phones have brought for their owners a number of new headaches.
Some people will __________ in the middle due to their lack of a strong will once they encounter any difficulty.