Sentence:  If you've picked up a secondhand one, you should invest $4.00 for a microwave leak tester. The one I have has a little smiley face and a little frowning face. If the smiley face lights up when you pass it in front of the turned-on microwave, then you can <WSD>nuke</WSD> with impunity. 
Meaning of the word marked with <WSD> tags:  To cook in a microwave oven.