Don’t lose heart_______you fail.
—Do you know Lily has gone to London?—Oh,________I haven't seen her these days.
Jane is an honest girl;I say it,________I don't like her.
Six people were killed in the riot(暴乱),a policeman________.
He tried his best to solve the problem,________difficult it was.
On the bus I saw a student I thought was your brother.