戒备的用英语怎么说？

戒备的

• jealous

例句

• He wears the guard on his expression. 他脸部带有戒备的神情。
• Suddenly we heard the shrieks of unwary animals taken by surprise. 突然我们听到了无戒备的动物遭突袭的尖叫声.
• He had crept up on his unsuspecting victim from behind. 他从背后悄悄逼近了那毫无戒备的受害者。
• Due to a security alert, this train will not be stopping at Oxford Circus. 由于安全戒备的原因，该次列车在“牛津街口广场”站将不停留。