וַ֠יַּעַן הַמַּלְאָ֞ךְ הַדֹּבֵ֥ר בִּי֙ וַיֹּ֣אמֶר אֵלַ֔י הֲל֥וֹא יָדַ֖עְתָּ מָה־הֵ֣מָּה אֵ֑לֶּה וָאֹמַ֖ר לֹ֥א אֲדֹנִֽי׃
Then the angel that spoke with me answered and said unto me: ‘Knowest thou not what these are?’ And I said: ‘No, my lord.’
Read midrashic interpretation of Zechariah 4:5: and classical rabbinic exegesis.