Abstract: Methods of operating a charge trap nonvolatile memory device include operations to erase a first string of nonvolatile memory cells by selectively erasing even-numbered nonvolatile memory cells in the first string and then selectively erasing the odd-numbered nonvolatile memory cells in the first string, which may be interleaved with the even-numbered nonvolatile memory cells. This operation to selectively erase the even-numbered nonvolatile memory cells may include erasing the even-numbered nonvolatile memory cells while simultaneously biasing the odd-numbered nonvolatile memory cells in a blocking condition that inhibits erasure of the odd-numbered nonvolatile memory cells. The operation to selectively erase the odd-numbered nonvolatile memory cells may include erasing the odd-numbered nonvolatile memory cells while simultaneously biasing the even-numbered nonvolatile memory cells in a blocking condition that inhibits erasure of the even-numbered nonvolatile memory cells.