I feel so weak, I can't even lift my arm.
Meaning: This means that the person is very weak and is unable to move their arm.
Choice of Words: Weak means lacking physical strength. Can't is a contraction of 'cannot', which means that something is not possible. Even means also or in addition. Lift means to raise something up. Arm is the part of your body that you use to hold things.
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Related Expressions