It seems that we must once again clarify what questions should and should not be closed with the close reason:
Questions that can be answered using commonly-available references are off-topic. A list of these references can be found here: List of general references
A reference work is, in the words of Wiktionary, "[a] compendium of information, which is not intended to be read from beginning to end, and is compiled for ease of reference. Examples include encyclopedias and dictionaries." Generally speaking, as far as we are concerned here on EL&U, references are dictionaries, thesauri, corpora, and style guides.
Most notably, extremely basic questions are not necessarily answerable by a reference. We close questions when references are available because questioners will receive a better answer from a reference, not because they are too easy for us.
Moreover, if a questioner has mentioned consulting a reference work, it is probably a bad idea to close that question by referring the questioner to reference works. In such case, the questioner is confused by the reference work; we should seek to clarify the reference work.
Accordingly, when using this close reason, please consider carefully whether or not the question can be answered with one of the linked reference works. If it can not, please look for another close reason, or do not close the question.
Useful reading: Google is not General Reference