These natural parks are very important for preserving many animals, which would ______ run the risk of becoming extinct(灭绝的).
Everyone hopes that we can do something to make things better, so we can't help ______ under the stress.
You ______ be driven out of the school if you dare to cheat in the exam.
On hearing a great noise, Mike looked forward through the window _____ what happened outside the room.
We hadn't met for 20 years, but I recognized her_____ I saw her.
There were many more people who got injured in the big fire than _______.