When Peter speaks in public, he always has difficulty ______ the right things to say.

A. thinking of                       B. to think of                        C. thought of                        D. think of

When Peter speaks in public, he always has difficulty ______ the right things to say.

When Peter speaks in public, he always has difficulty ______ the right things to say.

1. A.
   thinking of
2. B.
   to think of
3. C.
   thought of
4. D.
   think of

 When Peter speaks in public, he always has difficulty ______ the right things to say.

A. thinking of                 B. to think of                C. thought of                D. think of