If nature doesn’t provide man with the necessary material, it is the laboratory _____ he will turn to for help.
The boy fell asleep where he ______,without undressing.
Some countries are increasing their use of natural gas, and other forms of ______.
Liping has never gone to Japan, but he speaks Japanese____ he were Japanese.
They have decided to ____ the household expenses to devote money to the disaster area.
Don't try to cheat in the exam — you will never ____ it.