My father worked day and night. Otherwise, there ________ no one to support the family.

He insisted that his plan _______ carried out at once. 

一Professor Li, ______the student start at once or wait a while?     一At once.

I ran all the way to school yesterday, otherwise I        late for the annual talent show.

---I was trying to carry out the plan, but I failed.---Well, you _________, for we were uncertain it would do ________.