unguarded
adj
1 not guarded 无防卫的; 无人守护的
The prisoner was left unguarded. 那犯人无人看守.
Never leave your luggage unguarded, ie unattended. 千万注意看好自己的行李.
2 (esp of a person and what he says) careless or indiscreet (尤指人及言语)粗心的, 不留神的, 不谨慎的
unguarded comments, criticisms, etc 轻率的评语、 批评等
catch sb in an unguarded moment 乘某人不备将其抓住.