Anthea and Ben are playing a game. Here are the rules:  1. There are $18$ apples placed on the table.  2. They each take turns removing apples. In each turn, the player must remove $1$, $2$, or $3$ apples.  3. The player who removes the last apple wins the game.  If Anthea goes first, how many apples should she take in the first turn so that she can make sure she will win the game? 
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