Common Mistakes : Difficulty

noun

.BAD: She had a difficulty in obtaining a visa .GOOD: She had difficulty (in) obtaining a visa

: (have difficulty/difficulties (in) doing sth (NOT a difficulty .Sometimes he has difficulty in making himself understood

.BAD: I have great difficulty to understand him .GOOD: I have great difficulty (in) understanding him

: (have difficulty/difficulties (in) doing sth (NOT to do .You should have no difficulty in passing the exam