失去

This rubber has lost its tone.

We don't know a good thing till we've lost it.

Her patience finally gave out.

She has lost her good looks.

lie insensible; lose consciousness; fall into a coma

lose confidence/meaning

lose hope; be bereft of hope

be discredited

be no longer effective/valid; cease to be in force

lose one's popularity

be stripped of power

lose/exhaust one's patience; get impatient

lose popular support

lose touch/contact (with); be out of touch (with sb)

lose one's senses; be bereft of reason

lose one's grip (of); lose control (of); get out of hand/control

relax one's vigilance

miss a chance/an opportunity

forfeit one's citizenship