21.   More recently problems have surfaced at Duracell.

22.   Other problems have since surfaced.

23.   Other problems surface when retention rates plummet.

24.   Other problems will no doubt surface in hearings by committees of the Assembly and the Senate.

25.   Problems have surfaced with environmental contamination from solvents used in rocket testing and the legacy of decades of nuclear testing at the Santa Susana Field Lab.

26.   Problems are already surfacing, experts caution.

27.   Problems have surfaced at several businesses recently.

28.   Political problems first surfaced when administration officials began to declare that North Korea had agreed to freeze its entire nuclear program.

29.   Problems surface, though, when our primary measure of that progress is the accumulation of wealth or the mere trappings of it.

30.   Such sobering problems rarely surfaced on the Clinton re-election campaign trail, where the public hardly saw a hint of concern from the relentlessly upbeat candidate.