Never believe anything ______ any other person has believed it. Use your own head.
Guess what! I came across my primary school science teacher this morning, ______ I have lost touch for almost 20 years.
After Tom had finished some paper work, he ______ interviewing the applicants.
It takes ______ to talk to others on the team when that might expose some of your own weaknesses or ignorance.
______her ambition of becoming a professional singer, she has been training very hard since an early age.
According to Darwin's Survival of the Fittest, only those species that were able to ______ the sudden great changes of their living conditions survived.