[Q]: Would the following sentence, by the strictest standards, be considered correct? They promised it to rain.
++++++++++
[A]: unacceptable


[Q]: Would the following sentence, by the strictest standards, be considered correct? Why do you think he left?
++++++++++
[A]: acceptable


[Q]: Would the following sentence, by the strictest standards, be considered correct? They have left.
++++++++++
[A]:
acceptable