We must be strict _________ our work and strict _________ourselves.

had told him the truth, he ______ so angry now．

is one of largestcountries in the world,secondonly to Russia

Lost in the mountains for three days, what the three men were able to do was the help of helicopters.

Fans let ________ a scream when their favorite singer-Jay Chou turned________ at the concert.[ ]