When working on the memorization of Greek verb endings, it's important to “see” (in your mind’s eye) what you say (outloud or silently) as you practice. Therefore, regarding the Greek diphthong “ει,” it seems preferable and wise to pronounce it phonetically the same as the identical diphthong in the English word “height,” as opposed to the phonetic sound in the English word “freight.” This is because the “ει” diphthong occurs within the 2nd and 3rd persons of "active voice" verb endings of the Indicative mode (-ει, -εις), later “lengthening” to -ῃ when used in the same persons in the Subjunctive mode (-ῃ,-ῃς). Since the phonetic sound of ῃ is the same as the diphthong in “freight,” it tends to confuse the usage of these separately occurring endings (“ει” in the Indicative; “ῃ” in the Subjunctive, also "middle/passive voice" Indicative 2nd sing.) if pronounced identically. Putting this ει diphthong into a memorable memorization context—as my beginning Greek professor humorously used to remind us: