Answer:
You must be very clear.
Explanation:
This is because if you are very clear there is no chance of misinterpretation or misunderstanding
Answer:
I appreciate that whoever she is, is smiling.
Explanation:
I would prefer that I knew why she was smiling, else ask her why, please.
The sentence "Moreover, it is probably just as valuable or more valuable to us now, than it was in the ancient past".
Answer:
C
Explanation:
He should take a quick break, so he can get a snack and respond to his texts before he goes back to studying.