She's less pleasant than the other teachers, often giving out more difficult assignments.

It was the most difficult assignment of his life to date.

The job, he now says, was "by far the most difficult assignment" of his legal career.

"Continue to challenge him with the most difficult assignments, he will excel."

It will certainly be a difficult assignment for the Bengals' defense.

A few guiding principles would help the task force in its difficult assignment.

Due to his successful track record, 47 is usually given the Agency's largest and most difficult assignments.

It wasn't an especially artistic performance, but these are two of the top four teams in the field, making for a difficult first assignment.

He had carried out one difficult assignment after another and allowed other men to take the credit.

Teachers would give them more difficult assignments than to junior high school students.