A or An?

There is…… apple tree in my garden. a or an? an a an

…… flying saucer landed in my garden. a or an? A An A

I had never seen…… allien before. a or an? an a an

Sheila is in …… space rocket. a or an? a an a

…… asteroid fell into the sea. a or an? An A An

…… UFO is heading to our planet. a or an? A An A

James is…… astronaut. a or an? an a an

I had never seen…… alien reading a book. a or an? an a an

He uses …… telescope to see the Moon. a or an? a an a

She always carries…… umbrella. a or an? an a an

The Earth is …… planet. a or an? a an a

This alien is listening to…… old song. a or an? an a an

I’m having…… egg for breakfast. a or an? an a an

I saw…… monster in the park yesterday. a or an? a an a

He is playing with …… fire truck. a or an? a an a