Assalaamu alaykum. What is meant by "Lower your gaze"? Actually, I try to obey it, but sometimes I become confused with the meaning as I am not an Arab. I know that looking at the forbidden things like the covered or uncovered private parts of others is prohibited, but my confusion is about the faces of girls. I am giving you some of the meaning which I am confused about. Just say which one is correct:
1. Totally avoid to look at the face twice or intentionally (along with the body)
2. Look at her face for less time and with no sexual or lustful thoughts, but totally avoid to take an intentional gaze at her chest, waist area, thigh area, any other tempting body area whether from the front or the back.
When I started obeying it, I tried to apply No.1. Then I thought two things; the first is that if it means totally avoiding or not looking at her face too and never look at her face twice intentionally, then how did our Prophet or his Companions use to recognize the women of their time regarding so many matters and so often. And secondly, the interpretation of the meaning of that Quranic verse is "Lower your gaze" or "Reduce some of your gaze". It is not 'refrain or avoid your gaze'. Then I thought that the actual Quranic verse also has the same kind of meaning, so then I switched to No. 2.
Actually, I need to and have to see the face of women for so many reasons, one of which is that I am unmarried and have to recognize women from places. So please do not refer me to other fatwas. I hope you could answer me very briefly with Quran and Hadith references. And if you could just tell me whether I am correct with No. 2?

All perfect praise be to Allah, The Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad, sallallahu ‘alayhi wa sallam, is His slave and Messenger. 

Lowering the gaze means avoiding to look at people's ‘Awrah (body parts that must be covered as per the Shariah) and all that may lead to Fitnah (temptation). Al-Qurtubi said, “It is obligatory to lower the gaze from looking at all that one is prohibited from looking at, and at whatever is feared to lead to Fitnah.” [Tafseer Al-Qurtubi, 12/223]

So it is incumbent on you to lower your gaze from looking at non-Mahram (marriageable) women. If your eyes fell on a non-Mahram woman, you have to avert your eyes from her. It is impermissible for you to look at the faces of non-Mahram women intentionally, even if it is without lust. The exception in this regard is when looking is needed, as when the suitor is looking at the face of the woman whom he wishes to propose to, the judge looking at the face of the female witness, looking at the woman's face while conducting sale transactions, and the like of the situations that require verifying the identity of the person. Some scholars held that it is permissible to look at the face of the non-Mahram woman without lust when Fitnah is not feared. However, the opinion adopted at Islamweb is to forbid this except when needed, as stated above. This opinion is more prudent and safer. Verily, lowering the gaze is among the most important means to guarding one's chastity and purity of the heart.

Allah knows best.