The train_____ when I_____ to the station.[ ]

Let’s ________ for a picnic tomorrow.

Can you show me _______ to use this kind of camera?-Sorry, I don’t know, _______.

The man in a black suit _______ be our youth worker. — I’m sure it _____ be him. I saw him in the laboratory building some minutes ago.

We can’t see ______ flowers in the picture.