大家好，這是在劍橋網路字典查到關於 turn 當 become 的意思的例句.. .
The weather has suddenly turned cold.
She turned pale and started to shiver.
The mood of the meeting turned solemn when the extent of the problem became kn own.
Keele, pop star turned business tycoon, has launched a new range of cosmetics.
為什麼前面的句子turn都是主動表示，就獨獨在最後一句是被動呢？ 求解..