I have a meeting soon.
　　I have an engagement1 soon.
　　I have an engagement very shortly2.
　　I have an date very shortly.

　　I think I'd better go now.
　　I think I should go now.
　　I think I ought to go now.
　　I think I must go now.

　　It's getting dark.
　　It's getting dark outside.

　　I've to go quite soon.
　　I must go quite soon.
　　I must leave quite soon.
　　I've got to go leave in a few minutes.

　　It was fun to get together again.
　　It was exciting to get together again.
　　It was exciting to talk to each other.