_____ it is very late now, the researchers are still working in the lab.
\_\_\_\__ it is very late now, the researchers are still working in the lab.
根据
The top of that mountain is always covered _____ snow.
The top of that mountain is always covered \_\_\_\__ snow.
（4分）配平反应方程式：____+____=____+____
（4分）配平反应方程式：\_\_\_\_+\_\_\_\_=\_\_\_\_+\_\_\_\_
Generally, snakes won’t attack humans _____ they are threatened with danger.
Generally, snakes won’t attack humans \_\_\_\__ they are threatened with danger.
Even if parents no longer live together, they each continue to be _____ for their children in the eye of the law.
Even if parents no longer live together, they each continue to be \_\_\_\__ for their children in the eye of the law.
The harder he worked, the most troubles he had in his early days as a scientist.
The harder he worked, the most troubles he had in his early days as a scientist.