Chinese mugwort or wormwood / moxa / to stop or cut short / phonetic "ai" or "i" / abbr. for 艾滋病[ai4 zi1 bing4], AIDS
Albert Einstein (Ø) cut himself, so he wanted to treat his wound with wormwood (艾) and mugwort (艾) in the airplane's bathroom (ai4). He finds that he accidentally used artificial lawn (艹) instead, and much worse, it has been used by someone else before. Quickly he uses a pair of pliers (乂) to draw out the artificial lawn again to stop (艾) getting aids (艾).