1
She has the voice of an angel.
Sign "angel" by fluttering your hands outward from your shoulders, followed by the sign for "voice" and a facial expression showing awe or appreciation for the beautiful sound.
2
Look at the angel on top of the Christmas tree.
Use the sign for "angel" before signing "tree," then point upward or place the sign high up to establish the location of the angel resting on top of the tree.
3
You are an angel for helping me.
Point to the person, sign "angel," and then sign "help." Make sure your facial expression conveys genuine gratitude while gracefully fluttering your hands outward.