________ on their last legs, the enemies still thought they were unconquerable.
I don’t doubt _____ he is a brilliant scientist, but can he teach?
Criticism and self-criticism is necessary _____ it helps us to correct our mistakes.
_____ or not we had a baby, we couldn’t survive only on my salary.
_____ you are familiar with the author’s ideas, try reading all the sections as quickly as you possibly can.
_____ he works hard, I don’t mind when he finishes the experiment.