1 . I _______ him three years ago, but this morning I heard from him.

A．paid off

B．lost track of

C．suffered from

D．was concerned about

2 . Richard was called in by the police to answer questions          the disappearance of Thomas Riley, whose relatives were           his present situation.

A．concerning; concerning about	B．concerning; concerned about
C．concerned；concerning about	D．concerned; concerned about