Answer: Long-a sound:
Awake, motivate, praise, braces, display, stray, ashamed, betray, afraid, remain, sway, sway, training, terrain, explain, stale, waist.
Long-e sound: Feast, greet, disease, repeat, thief, betray, beneath, sheepish, remain, niece, release, freedom, eager, succeed, sleeve, upheavel.
Explanation: