Students should respect teachers and parents _______ just thinking for themselves.
Sometimes proper answers are not far to seek ______ food safety problems.
In that school, English is compulsory for all students, but French and Russian are ______.
Would you like tea or coffee?--_____, thank you. I’ve just had some water.
We can never expect ____ bluer sky unless we create _____less polluted world.
—Can I use your laptop for a while?— ; any how I am not using it now.