To be at a loss as to what to do; not to know what course to take; to be bewildered and helpless.
突如其来的变故让他感到罔知所措，一时间失去了方向。
The sudden change of events left him at a loss, and for a moment he lost his direction.
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To be at a loss as to what to do; not to know what course to take; to be bewildered and helpless.