show up, turn up

[John]

Are these all OK and natural?

1. It's my mother's birthday party. She'll be very disappointed if I don't show/turn up.
2. She showed/turned up twenty minutes late for class.
3. I/He failed to show/turn up for the meeting (on) Monday morning.

Thanks.

[Rusty]

Are these all OK and natural?

1. It's my mother's birthday party. She'll be very disappointed if I don't show/turn up.
2. She showed/turned up twenty minutes late for class.
3. I/He failed to show/turn up for the meeting (on) Monday morning.

Thanks.

They are all OK. The meaning is only slightly different. Show up put the responsibility on the subject/actor. Turn up is less definite, similar to: "it happened").